Revert of Componentize TemplateURLService

chrome/browser/search_engines/template_url_service.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/search_engines/template_url_service.h"
+
+#include <algorithm>
+#include <utility>
+
+#include "base/auto_reset.h"
+#include "base/command_line.h"
+#include "base/compiler_specific.h"
+#include "base/guid.h"
+#include "base/i18n/case_conversion.h"
+#include "base/memory/scoped_vector.h"
+#include "base/metrics/histogram.h"
+#include "base/prefs/pref_service.h"
+#include "base/stl_util.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/time/time.h"
+#include "chrome/browser/search_engines/search_host_to_urls_map.h"
+#include "chrome/browser/search_engines/template_url_service_client.h"
+#include "chrome/browser/search_engines/template_url_service_observer.h"
+#include "chrome/browser/search_engines/util.h"
+#include "components/rappor/rappor_service.h"
+#include "components/search_engines/search_engines_pref_names.h"
+#include "components/search_engines/search_terms_data.h"
+#include "components/search_engines/template_url.h"
+#include "components/search_engines/template_url_prepopulate_data.h"
+#include "components/url_fixer/url_fixer.h"
+#include "net/base/net_util.h"
+#include "net/base/registry_controlled_domains/registry_controlled_domain.h"
+#include "sync/api/sync_change.h"
+#include "sync/api/sync_error_factory.h"
+#include "sync/protocol/search_engine_specifics.pb.h"
+#include "sync/protocol/sync.pb.h"
+#include "url/gurl.h"
+
+typedef SearchHostToURLsMap::TemplateURLSet TemplateURLSet;
+typedef TemplateURLService::SyncDataMap SyncDataMap;
+
+namespace {
+
+bool IdenticalSyncGUIDs(const TemplateURLData* data, const TemplateURL* turl) {
+  if (!data || !turl)
+    return !data && !turl;
+
+  return data->sync_guid == turl->sync_guid();
+}
+
+const char kDeleteSyncedEngineHistogramName[] =
+    "Search.DeleteSyncedSearchEngine";
+
+// Values for an enumerated histogram used to track whenever an ACTION_DELETE is
+// sent to the server for search engines.
+enum DeleteSyncedSearchEngineEvent {
+  DELETE_ENGINE_USER_ACTION,
+  DELETE_ENGINE_PRE_SYNC,
+  DELETE_ENGINE_EMPTY_FIELD,
+  DELETE_ENGINE_MAX,
+};
+
+// Returns true iff the change in |change_list| at index |i| should not be sent
+// up to the server based on its GUIDs presence in |sync_data| or when compared
+// to changes after it in |change_list|.
+// The criteria is:
+//  1) It is an ACTION_UPDATE or ACTION_DELETE and the sync_guid associated
+//     with it is NOT found in |sync_data|. We can only update and remove
+//     entries that were originally from the Sync server.
+//  2) It is an ACTION_ADD and the sync_guid associated with it is found in
+//     |sync_data|. We cannot re-add entries that Sync already knew about.
+//  3) There is an update after an update for the same GUID. We prune earlier
+//     ones just to save bandwidth (Sync would normally coalesce them).
+bool ShouldRemoveSyncChange(size_t index,
+                            syncer::SyncChangeList* change_list,
+                            const SyncDataMap* sync_data) {
+  DCHECK(index < change_list->size());
+  const syncer::SyncChange& change_i = (*change_list)[index];
+  const std::string guid = change_i.sync_data().GetSpecifics()
+      .search_engine().sync_guid();
+  syncer::SyncChange::SyncChangeType type = change_i.change_type();
+  if ((type == syncer::SyncChange::ACTION_UPDATE ||
+       type == syncer::SyncChange::ACTION_DELETE) &&
+       sync_data->find(guid) == sync_data->end())
+    return true;
+  if (type == syncer::SyncChange::ACTION_ADD &&
+      sync_data->find(guid) != sync_data->end())
+    return true;
+  if (type == syncer::SyncChange::ACTION_UPDATE) {
+    for (size_t j = index + 1; j < change_list->size(); j++) {
+      const syncer::SyncChange& change_j = (*change_list)[j];
+      if ((syncer::SyncChange::ACTION_UPDATE == change_j.change_type()) &&
+          (change_j.sync_data().GetSpecifics().search_engine().sync_guid() ==
+              guid))
+        return true;
+    }
+  }
+  return false;
+}
+
+// Remove SyncChanges that should not be sent to the server from |change_list|.
+// This is done to eliminate incorrect SyncChanges added by the merge and
+// conflict resolution logic when it is unsure of whether or not an entry is new
+// from Sync or originally from the local model. This also removes changes that
+// would be otherwise be coalesced by Sync in order to save bandwidth.
+void PruneSyncChanges(const SyncDataMap* sync_data,
+                      syncer::SyncChangeList* change_list) {
+  for (size_t i = 0; i < change_list->size(); ) {
+    if (ShouldRemoveSyncChange(i, change_list, sync_data))
+      change_list->erase(change_list->begin() + i);
+    else
+      ++i;
+  }
+}
+
+// Returns true if |turl|'s GUID is not found inside |sync_data|. This is to be
+// used in MergeDataAndStartSyncing to differentiate between TemplateURLs from
+// Sync and TemplateURLs that were initially local, assuming |sync_data| is the
+// |initial_sync_data| parameter.
+bool IsFromSync(const TemplateURL* turl, const SyncDataMap& sync_data) {
+  return !!sync_data.count(turl->sync_guid());
+}
+
+// Log the number of instances of a keyword that exist, with zero or more
+// underscores, which could occur as the result of conflict resolution.
+void LogDuplicatesHistogram(
+    const TemplateURLService::TemplateURLVector& template_urls) {
+  std::map<std::string, int> duplicates;
+  for (TemplateURLService::TemplateURLVector::const_iterator it =
+      template_urls.begin(); it != template_urls.end(); ++it) {
+    std::string keyword = base::UTF16ToASCII((*it)->keyword());
+    base::TrimString(keyword, "_", &keyword);
+    duplicates[keyword]++;
+  }
+
+  // Count the keywords with duplicates.
+  int num_dupes = 0;
+  for (std::map<std::string, int>::const_iterator it = duplicates.begin();
+      it != duplicates.end(); ++it) {
+    if (it->second > 1)
+      num_dupes++;
+  }
+
+  UMA_HISTOGRAM_COUNTS_100("Search.SearchEngineDuplicateCounts", num_dupes);
+}
+
+}  // namespace
+
+
+// TemplateURLService::LessWithPrefix -----------------------------------------
+
+class TemplateURLService::LessWithPrefix {
+ public:
+  // We want to find the set of keywords that begin with a prefix.  The STL
+  // algorithms will return the set of elements that are "equal to" the
+  // prefix, where "equal(x, y)" means "!(cmp(x, y) || cmp(y, x))".  When
+  // cmp() is the typical std::less<>, this results in lexicographic equality;
+  // we need to extend this to mark a prefix as "not less than" a keyword it
+  // begins, which will cause the desired elements to be considered "equal to"
+  // the prefix.  Note: this is still a strict weak ordering, as required by
+  // equal_range() (though I will not prove that here).
+  //
+  // Unfortunately the calling convention is not "prefix and element" but
+  // rather "two elements", so we pass the prefix as a fake "element" which has
+  // a NULL KeywordDataElement pointer.
+  bool operator()(const KeywordToTemplateMap::value_type& elem1,
+                  const KeywordToTemplateMap::value_type& elem2) const {
+    return (elem1.second == NULL) ?
+        (elem2.first.compare(0, elem1.first.length(), elem1.first) > 0) :
+        (elem1.first < elem2.first);
+  }
+};
+
+
+// TemplateURLService ---------------------------------------------------------
+
+TemplateURLService::TemplateURLService(
+    PrefService* prefs,
+    scoped_ptr<SearchTermsData> search_terms_data,
+    KeywordWebDataService* web_data_service,
+    scoped_ptr<TemplateURLServiceClient> client,
+    GoogleURLTracker* google_url_tracker,
+    rappor::RapporService* rappor_service,
+    const base::Closure& dsp_change_callback)
+    : prefs_(prefs),
+      search_terms_data_(search_terms_data.Pass()),
+      web_data_service_(web_data_service),
+      client_(client.Pass()),
+      google_url_tracker_(google_url_tracker),
+      rappor_service_(rappor_service),
+      dsp_change_callback_(dsp_change_callback),
+      provider_map_(new SearchHostToURLsMap),
+      loaded_(false),
+      load_failed_(false),
+      load_handle_(0),
+      default_search_provider_(NULL),
+      next_id_(kInvalidTemplateURLID + 1),
+      time_provider_(&base::Time::Now),
+      models_associated_(false),
+      processing_syncer_changes_(false),
+      dsp_change_origin_(DSP_CHANGE_OTHER),
+      default_search_manager_(
+          prefs_,
+          base::Bind(&TemplateURLService::OnDefaultSearchChange,
+                     base::Unretained(this))) {
+  DCHECK(search_terms_data_);
+  Init(NULL, 0);
+}
+
+TemplateURLService::TemplateURLService(const Initializer* initializers,
+                                       const int count)
+    : prefs_(NULL),
+      search_terms_data_(new SearchTermsData),
+      web_data_service_(NULL),
+      google_url_tracker_(NULL),
+      rappor_service_(NULL),
+      provider_map_(new SearchHostToURLsMap),
+      loaded_(false),
+      load_failed_(false),
+      load_handle_(0),
+      default_search_provider_(NULL),
+      next_id_(kInvalidTemplateURLID + 1),
+      time_provider_(&base::Time::Now),
+      models_associated_(false),
+      processing_syncer_changes_(false),
+      dsp_change_origin_(DSP_CHANGE_OTHER),
+      default_search_manager_(
+          prefs_,
+          base::Bind(&TemplateURLService::OnDefaultSearchChange,
+                     base::Unretained(this))) {
+  Init(initializers, count);
+}
+
+TemplateURLService::~TemplateURLService() {
+  // |web_data_service_| should be deleted during Shutdown().
+  DCHECK(!web_data_service_);
+  STLDeleteElements(&template_urls_);
+}
+
+// static
+bool TemplateURLService::LoadDefaultSearchProviderFromPrefs(
+    PrefService* prefs,
+    scoped_ptr<TemplateURLData>* default_provider_data,
+    bool* is_managed) {
+  if (!prefs || !prefs->HasPrefPath(prefs::kDefaultSearchProviderSearchURL) ||
+      !prefs->HasPrefPath(prefs::kDefaultSearchProviderKeyword))
+    return false;
+
+  const PrefService::Preference* pref =
+      prefs->FindPreference(prefs::kDefaultSearchProviderSearchURL);
+  *is_managed = pref && pref->IsManaged();
+
+  if (!prefs->GetBoolean(prefs::kDefaultSearchProviderEnabled)) {
+    // The user doesn't want a default search provider.
+    default_provider_data->reset(NULL);
+    return true;
+  }
+
+  base::string16 name =
+      base::UTF8ToUTF16(prefs->GetString(prefs::kDefaultSearchProviderName));
+  base::string16 keyword =
+      base::UTF8ToUTF16(prefs->GetString(prefs::kDefaultSearchProviderKeyword));
+  if (keyword.empty())
+    return false;
+  std::string search_url =
+      prefs->GetString(prefs::kDefaultSearchProviderSearchURL);
+  // Force URL to be non-empty.  We've never supported this case, but past bugs
+  // might have resulted in it slipping through; eventually this code can be
+  // replaced with a DCHECK(!search_url.empty());.
+  if (search_url.empty())
+    return false;
+  std::string suggest_url =
+      prefs->GetString(prefs::kDefaultSearchProviderSuggestURL);
+  std::string instant_url =
+      prefs->GetString(prefs::kDefaultSearchProviderInstantURL);
+  std::string image_url =
+      prefs->GetString(prefs::kDefaultSearchProviderImageURL);
+  std::string new_tab_url =
+      prefs->GetString(prefs::kDefaultSearchProviderNewTabURL);
+  std::string search_url_post_params =
+      prefs->GetString(prefs::kDefaultSearchProviderSearchURLPostParams);
+  std::string suggest_url_post_params =
+      prefs->GetString(prefs::kDefaultSearchProviderSuggestURLPostParams);
+  std::string instant_url_post_params =
+      prefs->GetString(prefs::kDefaultSearchProviderInstantURLPostParams);
+  std::string image_url_post_params =
+      prefs->GetString(prefs::kDefaultSearchProviderImageURLPostParams);
+  std::string icon_url =
+      prefs->GetString(prefs::kDefaultSearchProviderIconURL);
+  std::string encodings =
+      prefs->GetString(prefs::kDefaultSearchProviderEncodings);
+  std::string id_string = prefs->GetString(prefs::kDefaultSearchProviderID);
+  std::string prepopulate_id =
+      prefs->GetString(prefs::kDefaultSearchProviderPrepopulateID);
+  const base::ListValue* alternate_urls =
+      prefs->GetList(prefs::kDefaultSearchProviderAlternateURLs);
+  std::string search_terms_replacement_key = prefs->GetString(
+      prefs::kDefaultSearchProviderSearchTermsReplacementKey);
+
+  default_provider_data->reset(new TemplateURLData);
+  (*default_provider_data)->short_name = name;
+  (*default_provider_data)->SetKeyword(keyword);
+  (*default_provider_data)->SetURL(search_url);
+  (*default_provider_data)->suggestions_url = suggest_url;
+  (*default_provider_data)->instant_url = instant_url;
+  (*default_provider_data)->image_url = image_url;
+  (*default_provider_data)->new_tab_url = new_tab_url;
+  (*default_provider_data)->search_url_post_params = search_url_post_params;
+  (*default_provider_data)->suggestions_url_post_params =
+      suggest_url_post_params;
+  (*default_provider_data)->instant_url_post_params = instant_url_post_params;
+  (*default_provider_data)->image_url_post_params = image_url_post_params;
+  (*default_provider_data)->favicon_url = GURL(icon_url);
+  (*default_provider_data)->show_in_default_list = true;
+  (*default_provider_data)->alternate_urls.clear();
+  for (size_t i = 0; i < alternate_urls->GetSize(); ++i) {
+    std::string alternate_url;
+    if (alternate_urls->GetString(i, &alternate_url))
+      (*default_provider_data)->alternate_urls.push_back(alternate_url);
+  }
+  (*default_provider_data)->search_terms_replacement_key =
+      search_terms_replacement_key;
+  base::SplitString(encodings, ';', &(*default_provider_data)->input_encodings);
+  if (!id_string.empty() && !*is_managed) {
+    int64 value;
+    base::StringToInt64(id_string, &value);
+    (*default_provider_data)->id = value;
+  }
+  if (!prepopulate_id.empty() && !*is_managed) {
+    int value;
+    base::StringToInt(prepopulate_id, &value);
+    (*default_provider_data)->prepopulate_id = value;
+  }
+  return true;
+}
+
+// static
+base::string16 TemplateURLService::CleanUserInputKeyword(
+    const base::string16& keyword) {
+  // Remove the scheme.
+  base::string16 result(base::i18n::ToLower(keyword));
+  base::TrimWhitespace(result, base::TRIM_ALL, &result);
+  url::Component scheme_component;
+  if (url::ExtractScheme(base::UTF16ToUTF8(keyword).c_str(),
+                         static_cast<int>(keyword.length()),
+                         &scheme_component)) {
+    // If the scheme isn't "http" or "https", bail.  The user isn't trying to
+    // type a web address, but rather an FTP, file:, or other scheme URL, or a
+    // search query with some sort of initial operator (e.g. "site:").
+    if (result.compare(0, scheme_component.end(),
+                       base::ASCIIToUTF16(url::kHttpScheme)) &&
+        result.compare(0, scheme_component.end(),
+                       base::ASCIIToUTF16(url::kHttpsScheme)))
+      return base::string16();
+
+    // Include trailing ':'.
+    result.erase(0, scheme_component.end() + 1);
+    // Many schemes usually have "//" after them, so strip it too.
+    const base::string16 after_scheme(base::ASCIIToUTF16("//"));
+    if (result.compare(0, after_scheme.length(), after_scheme) == 0)
+      result.erase(0, after_scheme.length());
+  }
+
+  // Remove leading "www.".
+  result = net::StripWWW(result);
+
+  // Remove trailing "/".
+  return (result.length() > 0 && result[result.length() - 1] == '/') ?
+      result.substr(0, result.length() - 1) : result;
+}
+
+// static
+void TemplateURLService::SaveDefaultSearchProviderToPrefs(
+    const TemplateURL* t_url,
+    PrefService* prefs) {
+  if (!prefs)
+    return;
+
+  bool enabled = false;
+  std::string search_url;
+  std::string suggest_url;
+  std::string instant_url;
+  std::string image_url;
+  std::string new_tab_url;
+  std::string search_url_post_params;
+  std::string suggest_url_post_params;
+  std::string instant_url_post_params;
+  std::string image_url_post_params;
+  std::string icon_url;
+  std::string encodings;
+  std::string short_name;
+  std::string keyword;
+  std::string id_string;
+  std::string prepopulate_id;
+  base::ListValue alternate_urls;
+  std::string search_terms_replacement_key;
+  if (t_url) {
+    DCHECK_EQ(TemplateURL::NORMAL, t_url->GetType());
+    enabled = true;
+    search_url = t_url->url();
+    suggest_url = t_url->suggestions_url();
+    instant_url = t_url->instant_url();
+    image_url = t_url->image_url();
+    new_tab_url = t_url->new_tab_url();
+    search_url_post_params = t_url->search_url_post_params();
+    suggest_url_post_params = t_url->suggestions_url_post_params();
+    instant_url_post_params = t_url->instant_url_post_params();
+    image_url_post_params = t_url->image_url_post_params();
+    GURL icon_gurl = t_url->favicon_url();
+    if (!icon_gurl.is_empty())
+      icon_url = icon_gurl.spec();
+    encodings = JoinString(t_url->input_encodings(), ';');
+    short_name = base::UTF16ToUTF8(t_url->short_name());
+    keyword = base::UTF16ToUTF8(t_url->keyword());
+    id_string = base::Int64ToString(t_url->id());
+    prepopulate_id = base::Int64ToString(t_url->prepopulate_id());
+    for (size_t i = 0; i < t_url->alternate_urls().size(); ++i)
+      alternate_urls.AppendString(t_url->alternate_urls()[i]);
+    search_terms_replacement_key = t_url->search_terms_replacement_key();
+  }
+  prefs->SetBoolean(prefs::kDefaultSearchProviderEnabled, enabled);
+  prefs->SetString(prefs::kDefaultSearchProviderSearchURL, search_url);
+  prefs->SetString(prefs::kDefaultSearchProviderSuggestURL, suggest_url);
+  prefs->SetString(prefs::kDefaultSearchProviderInstantURL, instant_url);
+  prefs->SetString(prefs::kDefaultSearchProviderImageURL, image_url);
+  prefs->SetString(prefs::kDefaultSearchProviderNewTabURL, new_tab_url);
+  prefs->SetString(prefs::kDefaultSearchProviderSearchURLPostParams,
+                   search_url_post_params);
+  prefs->SetString(prefs::kDefaultSearchProviderSuggestURLPostParams,
+                   suggest_url_post_params);
+  prefs->SetString(prefs::kDefaultSearchProviderInstantURLPostParams,
+                   instant_url_post_params);
+  prefs->SetString(prefs::kDefaultSearchProviderImageURLPostParams,
+                   image_url_post_params);
+  prefs->SetString(prefs::kDefaultSearchProviderIconURL, icon_url);
+  prefs->SetString(prefs::kDefaultSearchProviderEncodings, encodings);
+  prefs->SetString(prefs::kDefaultSearchProviderName, short_name);
+  prefs->SetString(prefs::kDefaultSearchProviderKeyword, keyword);
+  prefs->SetString(prefs::kDefaultSearchProviderID, id_string);
+  prefs->SetString(prefs::kDefaultSearchProviderPrepopulateID, prepopulate_id);
+  prefs->Set(prefs::kDefaultSearchProviderAlternateURLs, alternate_urls);
+  prefs->SetString(prefs::kDefaultSearchProviderSearchTermsReplacementKey,
+      search_terms_replacement_key);
+}
+
+bool TemplateURLService::CanReplaceKeyword(
+    const base::string16& keyword,
+    const GURL& url,
+    TemplateURL** template_url_to_replace) {
+  DCHECK(!keyword.empty());  // This should only be called for non-empty
+                             // keywords. If we need to support empty kewords
+                             // the code needs to change slightly.
+  TemplateURL* existing_url = GetTemplateURLForKeyword(keyword);
+  if (template_url_to_replace)
+    *template_url_to_replace = existing_url;
+  if (existing_url) {
+    // We already have a TemplateURL for this keyword. Only allow it to be
+    // replaced if the TemplateURL can be replaced.
+    return CanReplace(existing_url);
+  }
+
+  // We don't have a TemplateURL with keyword. Only allow a new one if there
+  // isn't a TemplateURL for the specified host, or there is one but it can
+  // be replaced. We do this to ensure that if the user assigns a different
+  // keyword to a generated TemplateURL, we won't regenerate another keyword for
+  // the same host.
+  return !url.is_valid() || url.host().empty() ||
+      CanReplaceKeywordForHost(url.host(), template_url_to_replace);
+}
+
+void TemplateURLService::FindMatchingKeywords(
+    const base::string16& prefix,
+    bool support_replacement_only,
+    TemplateURLVector* matches) {
+  // Sanity check args.
+  if (prefix.empty())
+    return;
+  DCHECK(matches != NULL);
+  DCHECK(matches->empty());  // The code for exact matches assumes this.
+
+  // Required for VS2010: http://connect.microsoft.com/VisualStudio/feedback/details/520043/error-converting-from-null-to-a-pointer-type-in-std-pair
+  TemplateURL* const kNullTemplateURL = NULL;
+
+  // Find matching keyword range.  Searches the element map for keywords
+  // beginning with |prefix| and stores the endpoints of the resulting set in
+  // |match_range|.
+  const std::pair<KeywordToTemplateMap::const_iterator,
+                  KeywordToTemplateMap::const_iterator> match_range(
+      std::equal_range(
+          keyword_to_template_map_.begin(), keyword_to_template_map_.end(),
+          KeywordToTemplateMap::value_type(prefix, kNullTemplateURL),
+          LessWithPrefix()));
+
+  // Return vector of matching keywords.
+  for (KeywordToTemplateMap::const_iterator i(match_range.first);
+       i != match_range.second; ++i) {
+    if (!support_replacement_only ||
+        i->second->url_ref().SupportsReplacement(search_terms_data()))
+      matches->push_back(i->second);
+  }
+}
+
+TemplateURL* TemplateURLService::GetTemplateURLForKeyword(
+    const base::string16& keyword) {
+  KeywordToTemplateMap::const_iterator elem(
+      keyword_to_template_map_.find(keyword));
+  if (elem != keyword_to_template_map_.end())
+    return elem->second;
+  return (!loaded_ &&
+      initial_default_search_provider_.get() &&
+      (initial_default_search_provider_->keyword() == keyword)) ?
+      initial_default_search_provider_.get() : NULL;
+}
+
+TemplateURL* TemplateURLService::GetTemplateURLForGUID(
+    const std::string& sync_guid) {
+  GUIDToTemplateMap::const_iterator elem(guid_to_template_map_.find(sync_guid));
+  if (elem != guid_to_template_map_.end())
+    return elem->second;
+  return (!loaded_ &&
+      initial_default_search_provider_.get() &&
+      (initial_default_search_provider_->sync_guid() == sync_guid)) ?
+      initial_default_search_provider_.get() : NULL;
+}
+
+TemplateURL* TemplateURLService::GetTemplateURLForHost(
+    const std::string& host) {
+  if (loaded_)
+    return provider_map_->GetTemplateURLForHost(host);
+  TemplateURL* initial_dsp = initial_default_search_provider_.get();
+  if (!initial_dsp)
+    return NULL;
+  return (initial_dsp->GenerateSearchURL(search_terms_data()).host() == host) ?
+      initial_dsp : NULL;
+}
+
+bool TemplateURLService::Add(TemplateURL* template_url) {
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+  if (!AddNoNotify(template_url, true))
+    return false;
+  NotifyObservers();
+  return true;
+}
+
+void TemplateURLService::AddWithOverrides(TemplateURL* template_url,
+                                          const base::string16& short_name,
+                                          const base::string16& keyword,
+                                          const std::string& url) {
+  DCHECK(!keyword.empty());
+  DCHECK(!url.empty());
+  template_url->data_.short_name = short_name;
+  template_url->data_.SetKeyword(keyword);
+  template_url->SetURL(url);
+  Add(template_url);
+}
+
+void TemplateURLService::AddExtensionControlledTURL(
+    TemplateURL* template_url,
+    scoped_ptr<TemplateURL::AssociatedExtensionInfo> info) {
+  DCHECK(loaded_);
+  DCHECK(template_url);
+  DCHECK_EQ(kInvalidTemplateURLID, template_url->id());
+  DCHECK(info);
+  DCHECK_NE(TemplateURL::NORMAL, info->type);
+  DCHECK_EQ(info->wants_to_be_default_engine,
+            template_url->show_in_default_list());
+  DCHECK(!FindTemplateURLForExtension(info->extension_id, info->type));
+  template_url->extension_info_.swap(info);
+
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+  if (AddNoNotify(template_url, true)) {
+    if (template_url->extension_info_->wants_to_be_default_engine)
+      UpdateExtensionDefaultSearchEngine();
+    NotifyObservers();
+  }
+}
+
+void TemplateURLService::Remove(TemplateURL* template_url) {
+  RemoveNoNotify(template_url);
+  NotifyObservers();
+}
+
+void TemplateURLService::RemoveExtensionControlledTURL(
+    const std::string& extension_id,
+    TemplateURL::Type type) {
+  DCHECK(loaded_);
+  TemplateURL* url = FindTemplateURLForExtension(extension_id, type);
+  if (!url)
+    return;
+  // NULL this out so that we can call RemoveNoNotify.
+  // UpdateExtensionDefaultSearchEngine will cause it to be reset.
+  if (default_search_provider_ == url)
+    default_search_provider_ = NULL;
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+  RemoveNoNotify(url);
+  UpdateExtensionDefaultSearchEngine();
+  NotifyObservers();
+}
+
+void TemplateURLService::RemoveAutoGeneratedSince(base::Time created_after) {
+  RemoveAutoGeneratedBetween(created_after, base::Time());
+}
+
+void TemplateURLService::RemoveAutoGeneratedBetween(base::Time created_after,
+                                                    base::Time created_before) {
+  RemoveAutoGeneratedForOriginBetween(GURL(), created_after, created_before);
+}
+
+void TemplateURLService::RemoveAutoGeneratedForOriginBetween(
+    const GURL& origin,
+    base::Time created_after,
+    base::Time created_before) {
+  GURL o(origin.GetOrigin());
+  bool should_notify = false;
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+  for (size_t i = 0; i < template_urls_.size();) {
+    if (template_urls_[i]->date_created() >= created_after &&
+        (created_before.is_null() ||
+         template_urls_[i]->date_created() < created_before) &&
+        CanReplace(template_urls_[i]) &&
+        (o.is_empty() ||
+         template_urls_[i]->GenerateSearchURL(
+             search_terms_data()).GetOrigin() == o)) {
+      RemoveNoNotify(template_urls_[i]);
+      should_notify = true;
+    } else {
+      ++i;
+    }
+  }
+  if (should_notify)
+    NotifyObservers();
+}
+
+void TemplateURLService::RegisterOmniboxKeyword(
+     const std::string& extension_id,
+     const std::string& extension_name,
+     const std::string& keyword,
+     const std::string& template_url_string) {
+  DCHECK(loaded_);
+
+  if (FindTemplateURLForExtension(extension_id,
+                                  TemplateURL::OMNIBOX_API_EXTENSION))
+    return;
+
+  TemplateURLData data;
+  data.short_name = base::UTF8ToUTF16(extension_name);
+  data.SetKeyword(base::UTF8ToUTF16(keyword));
+  data.SetURL(template_url_string);
+  TemplateURL* url = new TemplateURL(data);
+  scoped_ptr<TemplateURL::AssociatedExtensionInfo> info(
+      new TemplateURL::AssociatedExtensionInfo(
+          TemplateURL::OMNIBOX_API_EXTENSION, extension_id));
+  AddExtensionControlledTURL(url, info.Pass());
+}
+
+TemplateURLService::TemplateURLVector TemplateURLService::GetTemplateURLs() {
+  return template_urls_;
+}
+
+void TemplateURLService::IncrementUsageCount(TemplateURL* url) {
+  DCHECK(url);
+  // Extension-controlled search engines are not persisted.
+  if (url->GetType() == TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION)
+    return;
+  if (std::find(template_urls_.begin(), template_urls_.end(), url) ==
+      template_urls_.end())
+    return;
+  ++url->data_.usage_count;
+
+  if (web_data_service_)
+    web_data_service_->UpdateKeyword(url->data());
+}
+
+void TemplateURLService::ResetTemplateURL(TemplateURL* url,
+                                          const base::string16& title,
+                                          const base::string16& keyword,
+                                          const std::string& search_url) {
+  if (ResetTemplateURLNoNotify(url, title, keyword, search_url))
+    NotifyObservers();
+}
+
+bool TemplateURLService::CanMakeDefault(const TemplateURL* url) {
+  return
+      ((default_search_provider_source_ == DefaultSearchManager::FROM_USER) ||
+       (default_search_provider_source_ ==
+        DefaultSearchManager::FROM_FALLBACK)) &&
+      (url != GetDefaultSearchProvider()) &&
+      url->url_ref().SupportsReplacement(search_terms_data()) &&
+      (url->GetType() == TemplateURL::NORMAL);
+}
+
+void TemplateURLService::SetUserSelectedDefaultSearchProvider(
+    TemplateURL* url) {
+  // Omnibox keywords cannot be made default. Extension-controlled search
+  // engines can be made default only by the extension itself because they
+  // aren't persisted.
+  DCHECK(!url || (url->GetType() == TemplateURL::NORMAL));
+  if (load_failed_) {
+    // Skip the DefaultSearchManager, which will persist to user preferences.
+    if ((default_search_provider_source_ == DefaultSearchManager::FROM_USER) ||
+        (default_search_provider_source_ ==
+         DefaultSearchManager::FROM_FALLBACK)) {
+      ApplyDefaultSearchChange(url ? &url->data() : NULL,
+                               DefaultSearchManager::FROM_USER);
+    }
+  } else {
+    // We rely on the DefaultSearchManager to call OnDefaultSearchChange if, in
+    // fact, the effective DSE changes.
+    if (url)
+      default_search_manager_.SetUserSelectedDefaultSearchEngine(url->data());
+    else
+      default_search_manager_.ClearUserSelectedDefaultSearchEngine();
+  }
+}
+
+TemplateURL* TemplateURLService::GetDefaultSearchProvider() {
+  return loaded_ ?
+    default_search_provider_ : initial_default_search_provider_.get();
+}
+
+bool TemplateURLService::IsSearchResultsPageFromDefaultSearchProvider(
+    const GURL& url) {
+  TemplateURL* default_provider = GetDefaultSearchProvider();
+  return default_provider &&
+      default_provider->IsSearchURL(url, search_terms_data());
+}
+
+bool TemplateURLService::IsExtensionControlledDefaultSearch() {
+  return default_search_provider_source_ ==
+      DefaultSearchManager::FROM_EXTENSION;
+}
+
+void TemplateURLService::RepairPrepopulatedSearchEngines() {
+  // Can't clean DB if it hasn't been loaded.
+  DCHECK(loaded());
+
+  if ((default_search_provider_source_ == DefaultSearchManager::FROM_USER) ||
+      (default_search_provider_source_ ==
+          DefaultSearchManager::FROM_FALLBACK)) {
+    // Clear |default_search_provider_| in case we want to remove the engine it
+    // points to. This will get reset at the end of the function anyway.
+    default_search_provider_ = NULL;
+  }
+
+  size_t default_search_provider_index = 0;
+  ScopedVector<TemplateURLData> prepopulated_urls =
+      TemplateURLPrepopulateData::GetPrepopulatedEngines(
+          prefs_, &default_search_provider_index);
+  DCHECK(!prepopulated_urls.empty());
+  ActionsFromPrepopulateData actions(CreateActionsFromCurrentPrepopulateData(
+      &prepopulated_urls, template_urls_, default_search_provider_));
+
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+
+  // Remove items.
+  for (std::vector<TemplateURL*>::iterator i = actions.removed_engines.begin();
+       i < actions.removed_engines.end(); ++i)
+    RemoveNoNotify(*i);
+
+  // Edit items.
+  for (EditedEngines::iterator i(actions.edited_engines.begin());
+       i < actions.edited_engines.end(); ++i) {
+    TemplateURL new_values(i->second);
+    UpdateNoNotify(i->first, new_values);
+  }
+
+  // Add items.
+  for (std::vector<TemplateURLData>::const_iterator i =
+           actions.added_engines.begin();
+       i < actions.added_engines.end();
+       ++i) {
+    AddNoNotify(new TemplateURL(*i), true);
+  }
+
+  base::AutoReset<DefaultSearchChangeOrigin> change_origin(
+      &dsp_change_origin_, DSP_CHANGE_PROFILE_RESET);
+
+  default_search_manager_.ClearUserSelectedDefaultSearchEngine();
+
+  if (!default_search_provider_) {
+    // If the default search provider came from a user pref we would have been
+    // notified of the new (fallback-provided) value in
+    // ClearUserSelectedDefaultSearchEngine() above. Since we are here, the
+    // value was presumably originally a fallback value (which may have been
+    // repaired).
+    DefaultSearchManager::Source source;
+    const TemplateURLData* new_dse =
+        default_search_manager_.GetDefaultSearchEngine(&source);
+    // ApplyDefaultSearchChange will notify observers once it is done.
+    ApplyDefaultSearchChange(new_dse, source);
+  } else {
+    NotifyObservers();
+  }
+}
+
+void TemplateURLService::AddObserver(TemplateURLServiceObserver* observer) {
+  model_observers_.AddObserver(observer);
+}
+
+void TemplateURLService::RemoveObserver(TemplateURLServiceObserver* observer) {
+  model_observers_.RemoveObserver(observer);
+}
+
+void TemplateURLService::Load() {
+  if (loaded_ || load_handle_)
+    return;
+
+  if (web_data_service_)
+    load_handle_ = web_data_service_->GetKeywords(this);
+  else
+    ChangeToLoadedState();
+}
+
+scoped_ptr<TemplateURLService::Subscription>
+    TemplateURLService::RegisterOnLoadedCallback(
+        const base::Closure& callback) {
+  return loaded_ ?
+      scoped_ptr<TemplateURLService::Subscription>() :
+      on_loaded_callbacks_.Add(callback);
+}
+
+void TemplateURLService::OnWebDataServiceRequestDone(
+    KeywordWebDataService::Handle h,
+    const WDTypedResult* result) {
+  // Reset the load_handle so that we don't try and cancel the load in
+  // the destructor.
+  load_handle_ = 0;
+
+  if (!result) {
+    // Results are null if the database went away or (most likely) wasn't
+    // loaded.
+    load_failed_ = true;
+    web_data_service_ = NULL;
+    ChangeToLoadedState();
+    return;
+  }
+
+  TemplateURLVector template_urls;
+  int new_resource_keyword_version = 0;
+  GetSearchProvidersUsingKeywordResult(
+      *result,
+      web_data_service_.get(),
+      prefs_,
+      &template_urls,
+      (default_search_provider_source_ == DefaultSearchManager::FROM_USER) ?
+          initial_default_search_provider_.get() : NULL,
+      search_terms_data(),
+      &new_resource_keyword_version,
+      &pre_sync_deletes_);
+
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+
+  PatchMissingSyncGUIDs(&template_urls);
+  SetTemplateURLs(&template_urls);
+
+  // This initializes provider_map_ which should be done before
+  // calling UpdateKeywordSearchTermsForURL.
+  // This also calls NotifyObservers.
+  ChangeToLoadedState();
+
+  // Index any visits that occurred before we finished loading.
+  for (size_t i = 0; i < visits_to_add_.size(); ++i)
+    UpdateKeywordSearchTermsForURL(visits_to_add_[i]);
+  visits_to_add_.clear();
+
+  if (new_resource_keyword_version)
+    web_data_service_->SetBuiltinKeywordVersion(new_resource_keyword_version);
+
+  if (default_search_provider_) {
+    UMA_HISTOGRAM_ENUMERATION(
+        "Search.DefaultSearchProviderType",
+        TemplateURLPrepopulateData::GetEngineType(
+            *default_search_provider_, search_terms_data()),
+        SEARCH_ENGINE_MAX);
+
+    if (rappor_service_) {
+      rappor_service_->RecordSample(
+          "Search.DefaultSearchProvider",
+          rappor::ETLD_PLUS_ONE_RAPPOR_TYPE,
+          net::registry_controlled_domains::GetDomainAndRegistry(
+              default_search_provider_->url_ref().GetHost(search_terms_data()),
+              net::registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES));
+    }
+  }
+}
+
+base::string16 TemplateURLService::GetKeywordShortName(
+    const base::string16& keyword,
+    bool* is_omnibox_api_extension_keyword) {
+  const TemplateURL* template_url = GetTemplateURLForKeyword(keyword);
+
+  // TODO(sky): Once LocationBarView adds a listener to the TemplateURLService
+  // to track changes to the model, this should become a DCHECK.
+  if (template_url) {
+    *is_omnibox_api_extension_keyword =
+        template_url->GetType() == TemplateURL::OMNIBOX_API_EXTENSION;
+    return template_url->AdjustedShortNameForLocaleDirection();
+  }
+  *is_omnibox_api_extension_keyword = false;
+  return base::string16();
+}
+
+void TemplateURLService::OnHistoryURLVisited(const URLVisitedDetails& details) {
+  if (!loaded_)
+    visits_to_add_.push_back(details);
+  else
+    UpdateKeywordSearchTermsForURL(details);
+}
+
+void TemplateURLService::Shutdown() {
+  // This check has to be done at Shutdown() instead of in the dtor to ensure
+  // that no clients of KeywordWebDataService are holding ptrs to it after the
+  // first phase of the KeyedService Shutdown() process.
+  if (load_handle_) {
+    DCHECK(web_data_service_.get());
+    web_data_service_->CancelRequest(load_handle_);
+  }
+  web_data_service_ = NULL;
+}
+
+syncer::SyncDataList TemplateURLService::GetAllSyncData(
+    syncer::ModelType type) const {
+  DCHECK_EQ(syncer::SEARCH_ENGINES, type);
+
+  syncer::SyncDataList current_data;
+  for (TemplateURLVector::const_iterator iter = template_urls_.begin();
+      iter != template_urls_.end(); ++iter) {
+    // We don't sync keywords managed by policy.
+    if ((*iter)->created_by_policy())
+      continue;
+    // We don't sync extension-controlled search engines.
+    if ((*iter)->GetType() == TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION)
+      continue;
+    current_data.push_back(CreateSyncDataFromTemplateURL(**iter));
+  }
+
+  return current_data;
+}
+
+syncer::SyncError TemplateURLService::ProcessSyncChanges(
+    const tracked_objects::Location& from_here,
+    const syncer::SyncChangeList& change_list) {
+  if (!models_associated_) {
+    syncer::SyncError error(FROM_HERE,
+                            syncer::SyncError::DATATYPE_ERROR,
+                            "Models not yet associated.",
+                            syncer::SEARCH_ENGINES);
+    return error;
+  }
+  DCHECK(loaded_);
+
+  base::AutoReset<bool> processing_changes(&processing_syncer_changes_, true);
+
+  // We've started syncing, so set our origin member to the base Sync value.
+  // As we move through Sync Code, we may set this to increasingly specific
+  // origins so we can tell what exactly caused a DSP change.
+  base::AutoReset<DefaultSearchChangeOrigin> change_origin(&dsp_change_origin_,
+      DSP_CHANGE_SYNC_UNINTENTIONAL);
+
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+
+  syncer::SyncChangeList new_changes;
+  syncer::SyncError error;
+  for (syncer::SyncChangeList::const_iterator iter = change_list.begin();
+      iter != change_list.end(); ++iter) {
+    DCHECK_EQ(syncer::SEARCH_ENGINES, iter->sync_data().GetDataType());
+
+    std::string guid =
+        iter->sync_data().GetSpecifics().search_engine().sync_guid();
+    TemplateURL* existing_turl = GetTemplateURLForGUID(guid);
+    scoped_ptr<TemplateURL> turl(CreateTemplateURLFromTemplateURLAndSyncData(
+        prefs_, search_terms_data(), existing_turl, iter->sync_data(),
+        &new_changes));
+    if (!turl.get())
+      continue;
+
+    // Explicitly don't check for conflicts against extension keywords; in this
+    // case the functions which modify the keyword map know how to handle the
+    // conflicts.
+    // TODO(mpcomplete): If we allow editing extension keywords, then those will
+    // need to undergo conflict resolution.
+    TemplateURL* existing_keyword_turl =
+        FindNonExtensionTemplateURLForKeyword(turl->keyword());
+    if (iter->change_type() == syncer::SyncChange::ACTION_DELETE) {
+      if (!existing_turl) {
+        error = sync_error_factory_->CreateAndUploadError(
+            FROM_HERE,
+            "ProcessSyncChanges failed on ChangeType ACTION_DELETE");
+        continue;
+      }
+      if (existing_turl == GetDefaultSearchProvider()) {
+        // The only way Sync can attempt to delete the default search provider
+        // is if we had changed the kSyncedDefaultSearchProviderGUID
+        // preference, but perhaps it has not yet been received. To avoid
+        // situations where this has come in erroneously, we will un-delete
+        // the current default search from the Sync data. If the pref really
+        // does arrive later, then default search will change to the correct
+        // entry, but we'll have this extra entry sitting around. The result is
+        // not ideal, but it prevents a far more severe bug where the default is
+        // unexpectedly swapped to something else. The user can safely delete
+        // the extra entry again later, if they choose. Most users who do not
+        // look at the search engines UI will not notice this.
+        // Note that we append a special character to the end of the keyword in
+        // an attempt to avoid a ping-poinging situation where receiving clients
+        // may try to continually delete the resurrected entry.
+        base::string16 updated_keyword = UniquifyKeyword(*existing_turl, true);
+        TemplateURLData data(existing_turl->data());
+        data.SetKeyword(updated_keyword);
+        TemplateURL new_turl(data);
+        if (UpdateNoNotify(existing_turl, new_turl))
+          NotifyObservers();
+
+        syncer::SyncData sync_data = CreateSyncDataFromTemplateURL(new_turl);
+        new_changes.push_back(syncer::SyncChange(FROM_HERE,
+                                                 syncer::SyncChange::ACTION_ADD,
+                                                 sync_data));
+        // Ignore the delete attempt. This means we never end up resetting the
+        // default search provider due to an ACTION_DELETE from sync.
+        continue;
+      }
+
+      Remove(existing_turl);
+    } else if (iter->change_type() == syncer::SyncChange::ACTION_ADD) {
+      if (existing_turl) {
+        error = sync_error_factory_->CreateAndUploadError(
+            FROM_HERE,
+            "ProcessSyncChanges failed on ChangeType ACTION_ADD");
+        continue;
+      }
+      const std::string guid = turl->sync_guid();
+      if (existing_keyword_turl) {
+        // Resolve any conflicts so we can safely add the new entry.
+        ResolveSyncKeywordConflict(turl.get(), existing_keyword_turl,
+                                   &new_changes);
+      }
+      base::AutoReset<DefaultSearchChangeOrigin> change_origin(
+          &dsp_change_origin_, DSP_CHANGE_SYNC_ADD);
+      // Force the local ID to kInvalidTemplateURLID so we can add it.
+      TemplateURLData data(turl->data());
+      data.id = kInvalidTemplateURLID;
+      TemplateURL* added = new TemplateURL(data);
+      if (Add(added))
+        MaybeUpdateDSEAfterSync(added);
+    } else if (iter->change_type() == syncer::SyncChange::ACTION_UPDATE) {
+      if (!existing_turl) {
+        error = sync_error_factory_->CreateAndUploadError(
+            FROM_HERE,
+            "ProcessSyncChanges failed on ChangeType ACTION_UPDATE");
+        continue;
+      }
+      if (existing_keyword_turl && (existing_keyword_turl != existing_turl)) {
+        // Resolve any conflicts with other entries so we can safely update the
+        // keyword.
+        ResolveSyncKeywordConflict(turl.get(), existing_keyword_turl,
+                                   &new_changes);
+      }
+      if (UpdateNoNotify(existing_turl, *turl)) {
+        NotifyObservers();
+        MaybeUpdateDSEAfterSync(existing_turl);
+      }
+    } else {
+      // We've unexpectedly received an ACTION_INVALID.
+      error = sync_error_factory_->CreateAndUploadError(
+          FROM_HERE,
+          "ProcessSyncChanges received an ACTION_INVALID");
+    }
+  }
+
+  // If something went wrong, we want to prematurely exit to avoid pushing
+  // inconsistent data to Sync. We return the last error we received.
+  if (error.IsSet())
+    return error;
+
+  error = sync_processor_->ProcessSyncChanges(from_here, new_changes);
+
+  return error;
+}
+
+syncer::SyncMergeResult TemplateURLService::MergeDataAndStartSyncing(
+    syncer::ModelType type,
+    const syncer::SyncDataList& initial_sync_data,
+    scoped_ptr<syncer::SyncChangeProcessor> sync_processor,
+    scoped_ptr<syncer::SyncErrorFactory> sync_error_factory) {
+  DCHECK(loaded_);
+  DCHECK_EQ(type, syncer::SEARCH_ENGINES);
+  DCHECK(!sync_processor_.get());
+  DCHECK(sync_processor.get());
+  DCHECK(sync_error_factory.get());
+  syncer::SyncMergeResult merge_result(type);
+
+  // Disable sync if we failed to load.
+  if (load_failed_) {
+    merge_result.set_error(syncer::SyncError(
+        FROM_HERE, syncer::SyncError::DATATYPE_ERROR,
+        "Local database load failed.", syncer::SEARCH_ENGINES));
+    return merge_result;
+  }
+
+  sync_processor_ = sync_processor.Pass();
+  sync_error_factory_ = sync_error_factory.Pass();
+
+  // We do a lot of calls to Add/Remove/ResetTemplateURL here, so ensure we
+  // don't step on our own toes.
+  base::AutoReset<bool> processing_changes(&processing_syncer_changes_, true);
+
+  // We've started syncing, so set our origin member to the base Sync value.
+  // As we move through Sync Code, we may set this to increasingly specific
+  // origins so we can tell what exactly caused a DSP change.
+  base::AutoReset<DefaultSearchChangeOrigin> change_origin(&dsp_change_origin_,
+      DSP_CHANGE_SYNC_UNINTENTIONAL);
+
+  syncer::SyncChangeList new_changes;
+
+  // Build maps of our sync GUIDs to syncer::SyncData.
+  SyncDataMap local_data_map = CreateGUIDToSyncDataMap(
+      GetAllSyncData(syncer::SEARCH_ENGINES));
+  SyncDataMap sync_data_map = CreateGUIDToSyncDataMap(initial_sync_data);
+
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+
+  merge_result.set_num_items_before_association(local_data_map.size());
+  for (SyncDataMap::const_iterator iter = sync_data_map.begin();
+      iter != sync_data_map.end(); ++iter) {
+    TemplateURL* local_turl = GetTemplateURLForGUID(iter->first);
+    scoped_ptr<TemplateURL> sync_turl(
+        CreateTemplateURLFromTemplateURLAndSyncData(
+            prefs_, search_terms_data(), local_turl, iter->second,
+            &new_changes));
+    if (!sync_turl.get())
+      continue;
+
+    if (pre_sync_deletes_.find(sync_turl->sync_guid()) !=
+        pre_sync_deletes_.end()) {
+      // This entry was deleted before the initial sync began (possibly through
+      // preprocessing in TemplateURLService's loading code). Ignore it and send
+      // an ACTION_DELETE up to the server.
+      new_changes.push_back(
+          syncer::SyncChange(FROM_HERE,
+                             syncer::SyncChange::ACTION_DELETE,
+                             iter->second));
+      UMA_HISTOGRAM_ENUMERATION(kDeleteSyncedEngineHistogramName,
+          DELETE_ENGINE_PRE_SYNC, DELETE_ENGINE_MAX);
+      continue;
+    }
+
+    if (local_turl) {
+      DCHECK(IsFromSync(local_turl, sync_data_map));
+      // This local search engine is already synced. If the timestamp differs
+      // from Sync, we need to update locally or to the cloud. Note that if the
+      // timestamps are equal, we touch neither.
+      if (sync_turl->last_modified() > local_turl->last_modified()) {
+        // We've received an update from Sync. We should replace all synced
+        // fields in the local TemplateURL. Note that this includes the
+        // TemplateURLID and the TemplateURL may have to be reparsed. This
+        // also makes the local data's last_modified timestamp equal to Sync's,
+        // avoiding an Update on the next MergeData call.
+        if (UpdateNoNotify(local_turl, *sync_turl))
+          NotifyObservers();
+        merge_result.set_num_items_modified(
+            merge_result.num_items_modified() + 1);
+      } else if (sync_turl->last_modified() < local_turl->last_modified()) {
+        // Otherwise, we know we have newer data, so update Sync with our
+        // data fields.
+        new_changes.push_back(
+            syncer::SyncChange(FROM_HERE,
+                               syncer::SyncChange::ACTION_UPDATE,
+                               local_data_map[local_turl->sync_guid()]));
+      }
+      local_data_map.erase(iter->first);
+    } else {
+      // The search engine from the cloud has not been synced locally. Merge it
+      // into our local model. This will handle any conflicts with local (and
+      // already-synced) TemplateURLs. It will prefer to keep entries from Sync
+      // over not-yet-synced TemplateURLs.
+      MergeInSyncTemplateURL(sync_turl.get(), sync_data_map, &new_changes,
+                             &local_data_map, &merge_result);
+    }
+  }
+
+  // The remaining SyncData in local_data_map should be everything that needs to
+  // be pushed as ADDs to sync.
+  for (SyncDataMap::const_iterator iter = local_data_map.begin();
+      iter != local_data_map.end(); ++iter) {
+    new_changes.push_back(
+        syncer::SyncChange(FROM_HERE,
+                           syncer::SyncChange::ACTION_ADD,
+                           iter->second));
+  }
+
+  // Do some post-processing on the change list to ensure that we are sending
+  // valid changes to sync_processor_.
+  PruneSyncChanges(&sync_data_map, &new_changes);
+
+  LogDuplicatesHistogram(GetTemplateURLs());
+  merge_result.set_num_items_after_association(
+      GetAllSyncData(syncer::SEARCH_ENGINES).size());
+  merge_result.set_error(
+      sync_processor_->ProcessSyncChanges(FROM_HERE, new_changes));
+  if (merge_result.error().IsSet())
+    return merge_result;
+
+  // The ACTION_DELETEs from this set are processed. Empty it so we don't try to
+  // reuse them on the next call to MergeDataAndStartSyncing.
+  pre_sync_deletes_.clear();
+
+  models_associated_ = true;
+  return merge_result;
+}
+
+void TemplateURLService::StopSyncing(syncer::ModelType type) {
+  DCHECK_EQ(type, syncer::SEARCH_ENGINES);
+  models_associated_ = false;
+  sync_processor_.reset();
+  sync_error_factory_.reset();
+}
+
+void TemplateURLService::ProcessTemplateURLChange(
+    const tracked_objects::Location& from_here,
+    const TemplateURL* turl,
+    syncer::SyncChange::SyncChangeType type) {
+  DCHECK_NE(type, syncer::SyncChange::ACTION_INVALID);
+  DCHECK(turl);
+
+  if (!models_associated_)
+    return;  // Not syncing.
+
+  if (processing_syncer_changes_)
+    return;  // These are changes originating from us. Ignore.
+
+  // Avoid syncing keywords managed by policy.
+  if (turl->created_by_policy())
+    return;
+
+  // Avoid syncing extension-controlled search engines.
+  if (turl->GetType() == TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION)
+    return;
+
+  syncer::SyncChangeList changes;
+
+  syncer::SyncData sync_data = CreateSyncDataFromTemplateURL(*turl);
+  changes.push_back(syncer::SyncChange(from_here,
+                                       type,
+                                       sync_data));
+
+  sync_processor_->ProcessSyncChanges(FROM_HERE, changes);
+}
+
+// static
+syncer::SyncData TemplateURLService::CreateSyncDataFromTemplateURL(
+    const TemplateURL& turl) {
+  sync_pb::EntitySpecifics specifics;
+  sync_pb::SearchEngineSpecifics* se_specifics =
+      specifics.mutable_search_engine();
+  se_specifics->set_short_name(base::UTF16ToUTF8(turl.short_name()));
+  se_specifics->set_keyword(base::UTF16ToUTF8(turl.keyword()));
+  se_specifics->set_favicon_url(turl.favicon_url().spec());
+  se_specifics->set_url(turl.url());
+  se_specifics->set_safe_for_autoreplace(turl.safe_for_autoreplace());
+  se_specifics->set_originating_url(turl.originating_url().spec());
+  se_specifics->set_date_created(turl.date_created().ToInternalValue());
+  se_specifics->set_input_encodings(JoinString(turl.input_encodings(), ';'));
+  se_specifics->set_show_in_default_list(turl.show_in_default_list());
+  se_specifics->set_suggestions_url(turl.suggestions_url());
+  se_specifics->set_prepopulate_id(turl.prepopulate_id());
+  se_specifics->set_instant_url(turl.instant_url());
+  if (!turl.image_url().empty())
+    se_specifics->set_image_url(turl.image_url());
+  se_specifics->set_new_tab_url(turl.new_tab_url());
+  if (!turl.search_url_post_params().empty())
+    se_specifics->set_search_url_post_params(turl.search_url_post_params());
+  if (!turl.suggestions_url_post_params().empty()) {
+    se_specifics->set_suggestions_url_post_params(
+        turl.suggestions_url_post_params());
+  }
+  if (!turl.instant_url_post_params().empty())
+    se_specifics->set_instant_url_post_params(turl.instant_url_post_params());
+  if (!turl.image_url_post_params().empty())
+    se_specifics->set_image_url_post_params(turl.image_url_post_params());
+  se_specifics->set_last_modified(turl.last_modified().ToInternalValue());
+  se_specifics->set_sync_guid(turl.sync_guid());
+  for (size_t i = 0; i < turl.alternate_urls().size(); ++i)
+    se_specifics->add_alternate_urls(turl.alternate_urls()[i]);
+  se_specifics->set_search_terms_replacement_key(
+      turl.search_terms_replacement_key());
+
+  return syncer::SyncData::CreateLocalData(se_specifics->sync_guid(),
+                                           se_specifics->keyword(),
+                                           specifics);
+}
+
+// static
+TemplateURL* TemplateURLService::CreateTemplateURLFromTemplateURLAndSyncData(
+    PrefService* prefs,
+    const SearchTermsData& search_terms_data,
+    TemplateURL* existing_turl,
+    const syncer::SyncData& sync_data,
+    syncer::SyncChangeList* change_list) {
+  DCHECK(change_list);
+
+  sync_pb::SearchEngineSpecifics specifics =
+      sync_data.GetSpecifics().search_engine();
+
+  // Past bugs might have caused either of these fields to be empty.  Just
+  // delete this data off the server.
+  if (specifics.url().empty() || specifics.sync_guid().empty()) {
+    change_list->push_back(
+        syncer::SyncChange(FROM_HERE,
+                           syncer::SyncChange::ACTION_DELETE,
+                           sync_data));
+    UMA_HISTOGRAM_ENUMERATION(kDeleteSyncedEngineHistogramName,
+        DELETE_ENGINE_EMPTY_FIELD, DELETE_ENGINE_MAX);
+    return NULL;
+  }
+
+  TemplateURLData data(existing_turl ?
+      existing_turl->data() : TemplateURLData());
+  data.short_name = base::UTF8ToUTF16(specifics.short_name());
+  data.originating_url = GURL(specifics.originating_url());
+  base::string16 keyword(base::UTF8ToUTF16(specifics.keyword()));
+  // NOTE: Once this code has shipped in a couple of stable releases, we can
+  // probably remove the migration portion, comment out the
+  // "autogenerate_keyword" field entirely in the .proto file, and fold the
+  // empty keyword case into the "delete data" block above.
+  bool reset_keyword =
+      specifics.autogenerate_keyword() || specifics.keyword().empty();
+  if (reset_keyword)
+    keyword = base::ASCIIToUTF16("dummy");  // Will be replaced below.
+  DCHECK(!keyword.empty());
+  data.SetKeyword(keyword);
+  data.SetURL(specifics.url());
+  data.suggestions_url = specifics.suggestions_url();
+  data.instant_url = specifics.instant_url();
+  data.image_url = specifics.image_url();
+  data.new_tab_url = specifics.new_tab_url();
+  data.search_url_post_params = specifics.search_url_post_params();
+  data.suggestions_url_post_params = specifics.suggestions_url_post_params();
+  data.instant_url_post_params = specifics.instant_url_post_params();
+  data.image_url_post_params = specifics.image_url_post_params();
+  data.favicon_url = GURL(specifics.favicon_url());
+  data.show_in_default_list = specifics.show_in_default_list();
+  data.safe_for_autoreplace = specifics.safe_for_autoreplace();
+  base::SplitString(specifics.input_encodings(), ';', &data.input_encodings);
+  // If the server data has duplicate encodings, we'll want to push an update
+  // below to correct it.  Note that we also fix this in
+  // GetSearchProvidersUsingKeywordResult(), since otherwise we'd never correct
+  // local problems for clients which have disabled search engine sync.
+  bool deduped = DeDupeEncodings(&data.input_encodings);
+  data.date_created = base::Time::FromInternalValue(specifics.date_created());
+  data.last_modified = base::Time::FromInternalValue(specifics.last_modified());
+  data.prepopulate_id = specifics.prepopulate_id();
+  data.sync_guid = specifics.sync_guid();
+  data.alternate_urls.clear();
+  for (int i = 0; i < specifics.alternate_urls_size(); ++i)
+    data.alternate_urls.push_back(specifics.alternate_urls(i));
+  data.search_terms_replacement_key = specifics.search_terms_replacement_key();
+
+  TemplateURL* turl = new TemplateURL(data);
+  // If this TemplateURL matches a built-in prepopulated template URL, it's
+  // possible that sync is trying to modify fields that should not be touched.
+  // Revert these fields to the built-in values.
+  UpdateTemplateURLIfPrepopulated(turl, prefs);
+  DCHECK_NE(TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION, turl->GetType());
+  if (reset_keyword || deduped) {
+    if (reset_keyword)
+      turl->ResetKeywordIfNecessary(search_terms_data, true);
+    syncer::SyncData sync_data = CreateSyncDataFromTemplateURL(*turl);
+    change_list->push_back(syncer::SyncChange(FROM_HERE,
+                                              syncer::SyncChange::ACTION_UPDATE,
+                                              sync_data));
+  } else if (turl->IsGoogleSearchURLWithReplaceableKeyword(search_terms_data)) {
+    if (!existing_turl) {
+      // We're adding a new TemplateURL that uses the Google base URL, so set
+      // its keyword appropriately for the local environment.
+      turl->ResetKeywordIfNecessary(search_terms_data, false);
+    } else if (existing_turl->IsGoogleSearchURLWithReplaceableKeyword(
+        search_terms_data)) {
+      // Ignore keyword changes triggered by the Google base URL changing on
+      // another client.  If the base URL changes in this client as well, we'll
+      // pick that up separately at the appropriate time.  Otherwise, changing
+      // the keyword here could result in having the wrong keyword for the local
+      // environment.
+      turl->data_.SetKeyword(existing_turl->keyword());
+    }
+  }
+
+  return turl;
+}
+
+// static
+SyncDataMap TemplateURLService::CreateGUIDToSyncDataMap(
+    const syncer::SyncDataList& sync_data) {
+  SyncDataMap data_map;
+  for (syncer::SyncDataList::const_iterator i(sync_data.begin());
+       i != sync_data.end();
+       ++i)
+    data_map[i->GetSpecifics().search_engine().sync_guid()] = *i;
+  return data_map;
+}
+
+void TemplateURLService::SetKeywordSearchTermsForURL(
+    const TemplateURL* t_url,
+    const GURL& url,
+    const base::string16& term) {
+  if (client_)
+    client_->SetKeywordSearchTermsForURL(url, t_url->id(), term);
+}
+
+void TemplateURLService::Init(const Initializer* initializers,
+                              int num_initializers) {
+  if (client_)
+    client_->SetOwner(this);
+
+  // GoogleURLTracker is not created in tests.
+  if (google_url_tracker_) {
+    google_url_updated_subscription_ =
+        google_url_tracker_->RegisterCallback(base::Bind(
+            &TemplateURLService::OnGoogleURLUpdated, base::Unretained(this)));
+  }
+
+  if (prefs_) {
+    pref_change_registrar_.Init(prefs_);
+    pref_change_registrar_.Add(
+        prefs::kSyncedDefaultSearchProviderGUID,
+        base::Bind(
+            &TemplateURLService::OnSyncedDefaultSearchProviderGUIDChanged,
+            base::Unretained(this)));
+  }
+
+  DefaultSearchManager::Source source = DefaultSearchManager::FROM_USER;
+  TemplateURLData* dse =
+      default_search_manager_.GetDefaultSearchEngine(&source);
+  ApplyDefaultSearchChange(dse, source);
+
+  if (num_initializers > 0) {
+    // This path is only hit by test code and is used to simulate a loaded
+    // TemplateURLService.
+    ChangeToLoadedState();
+
+    // Add specific initializers, if any.
+    KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+    for (int i(0); i < num_initializers; ++i) {
+      DCHECK(initializers[i].keyword);
+      DCHECK(initializers[i].url);
+      DCHECK(initializers[i].content);
+
+      // TemplateURLService ends up owning the TemplateURL, don't try and free
+      // it.
+      TemplateURLData data;
+      data.short_name = base::UTF8ToUTF16(initializers[i].content);
+      data.SetKeyword(base::UTF8ToUTF16(initializers[i].keyword));
+      data.SetURL(initializers[i].url);
+      TemplateURL* template_url = new TemplateURL(data);
+      AddNoNotify(template_url, true);
+
+      // Set the first provided identifier to be the default.
+      if (i == 0)
+        default_search_manager_.SetUserSelectedDefaultSearchEngine(data);
+    }
+  }
+
+  // Request a server check for the correct Google URL if Google is the
+  // default search engine.
+  RequestGoogleURLTrackerServerCheckIfNecessary();
+}
+
+void TemplateURLService::RemoveFromMaps(TemplateURL* template_url) {
+  const base::string16& keyword = template_url->keyword();
+  DCHECK_NE(0U, keyword_to_template_map_.count(keyword));
+  if (keyword_to_template_map_[keyword] == template_url) {
+    // We need to check whether the keyword can now be provided by another
+    // TemplateURL.  See the comments in AddToMaps() for more information on
+    // extension keywords and how they can coexist with non-extension keywords.
+    // In the case of more than one extension, we use the most recently
+    // installed (which will be the most recently added, which will have the
+    // highest ID).
+    TemplateURL* best_fallback = NULL;
+    for (TemplateURLVector::const_iterator i(template_urls_.begin());
+         i != template_urls_.end(); ++i) {
+      TemplateURL* turl = *i;
+      // This next statement relies on the fact that there can only be one
+      // non-Omnibox API TemplateURL with a given keyword.
+      if ((turl != template_url) && (turl->keyword() == keyword) &&
+          (!best_fallback ||
+           (best_fallback->GetType() != TemplateURL::OMNIBOX_API_EXTENSION) ||
+           ((turl->GetType() == TemplateURL::OMNIBOX_API_EXTENSION) &&
+            (turl->id() > best_fallback->id()))))
+        best_fallback = turl;
+    }
+    if (best_fallback)
+      keyword_to_template_map_[keyword] = best_fallback;
+    else
+      keyword_to_template_map_.erase(keyword);
+  }
+
+  if (!template_url->sync_guid().empty())
+    guid_to_template_map_.erase(template_url->sync_guid());
+  // |provider_map_| is only initialized after loading has completed.
+  if (loaded_) {
+    provider_map_->Remove(template_url);
+  }
+}
+
+void TemplateURLService::AddToMaps(TemplateURL* template_url) {
+  bool template_url_is_omnibox_api =
+      template_url->GetType() == TemplateURL::OMNIBOX_API_EXTENSION;
+  const base::string16& keyword = template_url->keyword();
+  KeywordToTemplateMap::const_iterator i =
+      keyword_to_template_map_.find(keyword);
+  if (i == keyword_to_template_map_.end()) {
+    keyword_to_template_map_[keyword] = template_url;
+  } else {
+    const TemplateURL* existing_url = i->second;
+    // We should only have overlapping keywords when at least one comes from
+    // an extension.  In that case, the ranking order is:
+    //   Manually-modified keywords > extension keywords > replaceable keywords
+    // When there are multiple extensions, the last-added wins.
+    bool existing_url_is_omnibox_api =
+        existing_url->GetType() == TemplateURL::OMNIBOX_API_EXTENSION;
+    DCHECK(existing_url_is_omnibox_api || template_url_is_omnibox_api);
+    if (existing_url_is_omnibox_api ?
+        !CanReplace(template_url) : CanReplace(existing_url))
+      keyword_to_template_map_[keyword] = template_url;
+  }
+
+  if (!template_url->sync_guid().empty())
+    guid_to_template_map_[template_url->sync_guid()] = template_url;
+  // |provider_map_| is only initialized after loading has completed.
+  if (loaded_)
+    provider_map_->Add(template_url, search_terms_data());
+}
+
+// Helper for partition() call in next function.
+bool HasValidID(TemplateURL* t_url) {
+  return t_url->id() != kInvalidTemplateURLID;
+}
+
+void TemplateURLService::SetTemplateURLs(TemplateURLVector* urls) {
+  // Partition the URLs first, instead of implementing the loops below by simply
+  // scanning the input twice.  While it's not supposed to happen normally, it's
+  // possible for corrupt databases to return multiple entries with the same
+  // keyword.  In this case, the first loop may delete the first entry when
+  // adding the second.  If this happens, the second loop must not attempt to
+  // access the deleted entry.  Partitioning ensures this constraint.
+  TemplateURLVector::iterator first_invalid(
+      std::partition(urls->begin(), urls->end(), HasValidID));
+
+  // First, add the items that already have id's, so that the next_id_ gets
+  // properly set.
+  for (TemplateURLVector::const_iterator i = urls->begin(); i != first_invalid;
+       ++i) {
+    next_id_ = std::max(next_id_, (*i)->id());
+    AddNoNotify(*i, false);
+  }
+
+  // Next add the new items that don't have id's.
+  for (TemplateURLVector::const_iterator i = first_invalid; i != urls->end();
+       ++i)
+    AddNoNotify(*i, true);
+
+  // Clear the input vector to reduce the chance callers will try to use a
+  // (possibly deleted) entry.
+  urls->clear();
+}
+
+void TemplateURLService::ChangeToLoadedState() {
+  DCHECK(!loaded_);
+
+  provider_map_->Init(template_urls_, search_terms_data());
+  loaded_ = true;
+
+  // This will cause a call to NotifyObservers().
+  ApplyDefaultSearchChangeNoMetrics(
+      initial_default_search_provider_ ?
+          &initial_default_search_provider_->data() : NULL,
+      default_search_provider_source_);
+  initial_default_search_provider_.reset();
+  on_loaded_callbacks_.Notify();
+}
+
+bool TemplateURLService::CanReplaceKeywordForHost(
+    const std::string& host,
+    TemplateURL** to_replace) {
+  DCHECK(!to_replace || !*to_replace);
+  const TemplateURLSet* urls = provider_map_->GetURLsForHost(host);
+  if (!urls)
+    return true;
+  for (TemplateURLSet::const_iterator i(urls->begin()); i != urls->end(); ++i) {
+    if (CanReplace(*i)) {
+      if (to_replace)
+        *to_replace = *i;
+      return true;
+    }
+  }
+  return false;
+}
+
+bool TemplateURLService::CanReplace(const TemplateURL* t_url) {
+  return (t_url != default_search_provider_ && !t_url->show_in_default_list() &&
+          t_url->safe_for_autoreplace());
+}
+
+TemplateURL* TemplateURLService::FindNonExtensionTemplateURLForKeyword(
+    const base::string16& keyword) {
+  TemplateURL* keyword_turl = GetTemplateURLForKeyword(keyword);
+  if (!keyword_turl || (keyword_turl->GetType() == TemplateURL::NORMAL))
+    return keyword_turl;
+  // The extension keyword in the model may be hiding a replaceable
+  // non-extension keyword.  Look for it.
+  for (TemplateURLVector::const_iterator i(template_urls_.begin());
+       i != template_urls_.end(); ++i) {
+    if (((*i)->GetType() == TemplateURL::NORMAL) &&
+        ((*i)->keyword() == keyword))
+      return *i;
+  }
+  return NULL;
+}
+
+bool TemplateURLService::UpdateNoNotify(TemplateURL* existing_turl,
+                                        const TemplateURL& new_values) {
+  DCHECK(existing_turl);
+  if (std::find(template_urls_.begin(), template_urls_.end(), existing_turl) ==
+      template_urls_.end())
+    return false;
+
+  base::string16 old_keyword(existing_turl->keyword());
+  keyword_to_template_map_.erase(old_keyword);
+  if (!existing_turl->sync_guid().empty())
+    guid_to_template_map_.erase(existing_turl->sync_guid());
+
+  // |provider_map_| is only initialized after loading has completed.
+  if (loaded_)
+    provider_map_->Remove(existing_turl);
+
+  TemplateURLID previous_id = existing_turl->id();
+  existing_turl->CopyFrom(new_values);
+  existing_turl->data_.id = previous_id;
+
+  if (loaded_) {
+    provider_map_->Add(existing_turl, search_terms_data());
+  }
+
+  const base::string16& keyword = existing_turl->keyword();
+  KeywordToTemplateMap::const_iterator i =
+      keyword_to_template_map_.find(keyword);
+  if (i == keyword_to_template_map_.end()) {
+    keyword_to_template_map_[keyword] = existing_turl;
+  } else {
+    // We can theoretically reach here in two cases:
+    //   * There is an existing extension keyword and sync brings in a rename of
+    //     a non-extension keyword to match.  In this case we just need to pick
+    //     which keyword has priority to update the keyword map.
+    //   * Autogeneration of the keyword for a Google default search provider
+    //     at load time causes it to conflict with an existing keyword.  In this
+    //     case we delete the existing keyword if it's replaceable, or else undo
+    //     the change in keyword for |existing_turl|.
+    TemplateURL* existing_keyword_turl = i->second;
+    if (existing_keyword_turl->GetType() != TemplateURL::NORMAL) {
+      if (!CanReplace(existing_turl))
+        keyword_to_template_map_[keyword] = existing_turl;
+    } else {
+      if (CanReplace(existing_keyword_turl)) {
+        RemoveNoNotify(existing_keyword_turl);
+      } else {
+        existing_turl->data_.SetKeyword(old_keyword);
+        keyword_to_template_map_[old_keyword] = existing_turl;
+      }
+    }
+  }
+  if (!existing_turl->sync_guid().empty())
+    guid_to_template_map_[existing_turl->sync_guid()] = existing_turl;
+
+  if (web_data_service_)
+    web_data_service_->UpdateKeyword(existing_turl->data());
+
+  // Inform sync of the update.
+  ProcessTemplateURLChange(
+      FROM_HERE, existing_turl, syncer::SyncChange::ACTION_UPDATE);
+
+  if (default_search_provider_ == existing_turl &&
+      default_search_provider_source_ == DefaultSearchManager::FROM_USER) {
+    default_search_manager_.SetUserSelectedDefaultSearchEngine(
+        default_search_provider_->data());
+  }
+  return true;
+}
+
+// static
+void TemplateURLService::UpdateTemplateURLIfPrepopulated(
+    TemplateURL* template_url,
+    PrefService* prefs) {
+  int prepopulate_id = template_url->prepopulate_id();
+  if (template_url->prepopulate_id() == 0)
+    return;
+
+  size_t default_search_index;
+  ScopedVector<TemplateURLData> prepopulated_urls =
+      TemplateURLPrepopulateData::GetPrepopulatedEngines(
+          prefs, &default_search_index);
+
+  for (size_t i = 0; i < prepopulated_urls.size(); ++i) {
+    if (prepopulated_urls[i]->prepopulate_id == prepopulate_id) {
+      MergeIntoPrepopulatedEngineData(template_url, prepopulated_urls[i]);
+      template_url->CopyFrom(TemplateURL(*prepopulated_urls[i]));
+    }
+  }
+}
+
+void TemplateURLService::MaybeUpdateDSEAfterSync(TemplateURL* synced_turl) {
+  if (prefs_ &&
+      (synced_turl->sync_guid() ==
+          prefs_->GetString(prefs::kSyncedDefaultSearchProviderGUID))) {
+    default_search_manager_.SetUserSelectedDefaultSearchEngine(
+        synced_turl->data());
+  }
+}
+
+void TemplateURLService::UpdateKeywordSearchTermsForURL(
+    const URLVisitedDetails& details) {
+  if (!details.url.is_valid())
+    return;
+
+  const TemplateURLSet* urls_for_host =
+      provider_map_->GetURLsForHost(details.url.host());
+  if (!urls_for_host)
+    return;
+
+  for (TemplateURLSet::const_iterator i = urls_for_host->begin();
+       i != urls_for_host->end(); ++i) {
+    base::string16 search_terms;
+    if ((*i)->ExtractSearchTermsFromURL(details.url, search_terms_data(),
+                                        &search_terms) &&
+        !search_terms.empty()) {
+      if (details.is_keyword_transition) {
+        // The visit is the result of the user entering a keyword, generate a
+        // KEYWORD_GENERATED visit for the KEYWORD so that the keyword typed
+        // count is boosted.
+        AddTabToSearchVisit(**i);
+      }
+      SetKeywordSearchTermsForURL(*i, details.url, search_terms);
+    }
+  }
+}
+
+void TemplateURLService::AddTabToSearchVisit(const TemplateURL& t_url) {
+  // Only add visits for entries the user hasn't modified. If the user modified
+  // the entry the keyword may no longer correspond to the host name. It may be
+  // possible to do something more sophisticated here, but it's so rare as to
+  // not be worth it.
+  if (!t_url.safe_for_autoreplace())
+    return;
+
+  if (!client_)
+    return;
+
+  GURL url(
+      url_fixer::FixupURL(base::UTF16ToUTF8(t_url.keyword()), std::string()));
+  if (!url.is_valid())
+    return;
+
+  // Synthesize a visit for the keyword. This ensures the url for the keyword is
+  // autocompleted even if the user doesn't type the url in directly.
+  client_->AddKeywordGeneratedVisit(url);
+}
+
+void TemplateURLService::RequestGoogleURLTrackerServerCheckIfNecessary() {
+  if (default_search_provider_ &&
+      default_search_provider_->HasGoogleBaseURLs(search_terms_data()) &&
+      google_url_tracker_)
+    google_url_tracker_->RequestServerCheck(false);
+}
+
+void TemplateURLService::GoogleBaseURLChanged() {
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+  bool something_changed = false;
+  for (TemplateURLVector::iterator i(template_urls_.begin());
+       i != template_urls_.end(); ++i) {
+    TemplateURL* t_url = *i;
+    if (t_url->HasGoogleBaseURLs(search_terms_data())) {
+      TemplateURL updated_turl(t_url->data());
+      updated_turl.ResetKeywordIfNecessary(search_terms_data(), false);
+      KeywordToTemplateMap::const_iterator existing_entry =
+          keyword_to_template_map_.find(updated_turl.keyword());
+      if ((existing_entry != keyword_to_template_map_.end()) &&
+          (existing_entry->second != t_url)) {
+        // The new autogenerated keyword conflicts with another TemplateURL.
+        // Overwrite it if it's replaceable; otherwise, leave |t_url| using its
+        // current keyword.  (This will not prevent |t_url| from auto-updating
+        // the keyword in the future if the conflicting TemplateURL disappears.)
+        // Note that we must still update |t_url| in this case, or the
+        // |provider_map_| will not be updated correctly.
+        if (CanReplace(existing_entry->second))
+          RemoveNoNotify(existing_entry->second);
+        else
+          updated_turl.data_.SetKeyword(t_url->keyword());
+      }
+      something_changed = true;
+      // This will send the keyword change to sync.  Note that other clients
+      // need to reset the keyword to an appropriate local value when this
+      // change arrives; see CreateTemplateURLFromTemplateURLAndSyncData().
+      UpdateNoNotify(t_url, updated_turl);
+    }
+  }
+  if (something_changed)
+    NotifyObservers();
+}
+
+void TemplateURLService::OnGoogleURLUpdated(GURL old_url, GURL new_url) {
+  if (loaded_)
+    GoogleBaseURLChanged();
+}
+
+void TemplateURLService::OnDefaultSearchChange(
+    const TemplateURLData* data,
+    DefaultSearchManager::Source source) {
+  if (prefs_ && (source == DefaultSearchManager::FROM_USER) &&
+      ((source != default_search_provider_source_) ||
+       !IdenticalSyncGUIDs(data, GetDefaultSearchProvider()))) {
+    prefs_->SetString(prefs::kSyncedDefaultSearchProviderGUID, data->sync_guid);
+  }
+  ApplyDefaultSearchChange(data, source);
+}
+
+void TemplateURLService::ApplyDefaultSearchChange(
+    const TemplateURLData* data,
+    DefaultSearchManager::Source source) {
+  if (!ApplyDefaultSearchChangeNoMetrics(data, source))
+    return;
+
+  UMA_HISTOGRAM_ENUMERATION(
+      "Search.DefaultSearchChangeOrigin", dsp_change_origin_, DSP_CHANGE_MAX);
+
+  if (GetDefaultSearchProvider() &&
+      GetDefaultSearchProvider()->HasGoogleBaseURLs(search_terms_data()) &&
+      !dsp_change_callback_.is_null())
+    dsp_change_callback_.Run();
+}
+
+bool TemplateURLService::ApplyDefaultSearchChangeNoMetrics(
+    const TemplateURLData* data,
+    DefaultSearchManager::Source source) {
+  if (!loaded_) {
+    // Set |initial_default_search_provider_| from the preferences. This is
+    // mainly so we can hold ownership until we get to the point where the list
+    // of keywords from Web Data is the owner of everything including the
+    // default.
+    bool changed = TemplateURL::MatchesData(
+        initial_default_search_provider_.get(), data, search_terms_data());
+    initial_default_search_provider_.reset(
+        data ? new TemplateURL(*data) : NULL);
+    default_search_provider_source_ = source;
+    return changed;
+  }
+
+  // Prevent recursion if we update the value stored in default_search_manager_.
+  // Note that we exclude the case of data == NULL because that could cause a
+  // false positive for recursion when the initial_default_search_provider_ is
+  // NULL due to policy. We'll never actually get recursion with data == NULL.
+  if (source == default_search_provider_source_ && data != NULL &&
+      TemplateURL::MatchesData(default_search_provider_, data,
+                               search_terms_data()))
+    return false;
+
+  // This may be deleted later. Use exclusively for pointer comparison to detect
+  // a change.
+  TemplateURL* previous_default_search_engine = default_search_provider_;
+
+  KeywordWebDataService::BatchModeScoper scoper(web_data_service_.get());
+  if (default_search_provider_source_ == DefaultSearchManager::FROM_POLICY ||
+      source == DefaultSearchManager::FROM_POLICY) {
+    // We do this both to remove any no-longer-applicable policy-defined DSE as
+    // well as to add the new one, if appropriate.
+    UpdateProvidersCreatedByPolicy(
+        &template_urls_,
+        source == DefaultSearchManager::FROM_POLICY ? data : NULL);
+  }
+
+  if (!data) {
+    default_search_provider_ = NULL;
+  } else if (source == DefaultSearchManager::FROM_EXTENSION) {
+    default_search_provider_ = FindMatchingExtensionTemplateURL(
+        *data, TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION);
+  } else if (source == DefaultSearchManager::FROM_FALLBACK) {
+    default_search_provider_ =
+        FindPrepopulatedTemplateURL(data->prepopulate_id);
+    if (default_search_provider_) {
+      TemplateURLData update_data(*data);
+      update_data.sync_guid = default_search_provider_->sync_guid();
+      if (!default_search_provider_->safe_for_autoreplace()) {
+        update_data.safe_for_autoreplace = false;
+        update_data.SetKeyword(default_search_provider_->keyword());
+        update_data.short_name = default_search_provider_->short_name();
+      }
+      UpdateNoNotify(default_search_provider_, TemplateURL(update_data));
+    } else {
+      // Normally the prepopulated fallback should be present in
+      // |template_urls_|, but in a few cases it might not be:
+      // (1) Tests that initialize the TemplateURLService in peculiar ways.
+      // (2) If the user deleted the pre-populated default and we subsequently
+      // lost their user-selected value.
+      TemplateURL* new_dse = new TemplateURL(*data);
+      if (AddNoNotify(new_dse, true))
+        default_search_provider_ = new_dse;
+    }
+  } else if (source == DefaultSearchManager::FROM_USER) {
+    default_search_provider_ = GetTemplateURLForGUID(data->sync_guid);
+    if (!default_search_provider_ && data->prepopulate_id) {
+      default_search_provider_ =
+          FindPrepopulatedTemplateURL(data->prepopulate_id);
+    }
+    TemplateURLData new_data(*data);
+    new_data.show_in_default_list = true;
+    if (default_search_provider_) {
+      UpdateNoNotify(default_search_provider_, TemplateURL(new_data));
+    } else {
+      new_data.id = kInvalidTemplateURLID;
+      TemplateURL* new_dse = new TemplateURL(new_data);
+      if (AddNoNotify(new_dse, true))
+        default_search_provider_ = new_dse;
+    }
+    if (default_search_provider_ && prefs_) {
+      prefs_->SetString(prefs::kSyncedDefaultSearchProviderGUID,
+                        default_search_provider_->sync_guid());
+    }
+
+  }
+
+  default_search_provider_source_ = source;
+
+  bool changed = default_search_provider_ != previous_default_search_engine;
+  if (changed)
+    RequestGoogleURLTrackerServerCheckIfNecessary();
+
+  NotifyObservers();
+
+  return changed;
+}
+
+bool TemplateURLService::AddNoNotify(TemplateURL* template_url,
+                                     bool newly_adding) {
+  DCHECK(template_url);
+
+  if (newly_adding) {
+    DCHECK_EQ(kInvalidTemplateURLID, template_url->id());
+    DCHECK(std::find(template_urls_.begin(), template_urls_.end(),
+                     template_url) == template_urls_.end());
+    template_url->data_.id = ++next_id_;
+  }
+
+  template_url->ResetKeywordIfNecessary(search_terms_data(), false);
+  // Check whether |template_url|'s keyword conflicts with any already in the
+  // model.
+  TemplateURL* existing_keyword_turl =
+      GetTemplateURLForKeyword(template_url->keyword());
+
+  // Check whether |template_url|'s keyword conflicts with any already in the
+  // model.  Note that we can reach here during the loading phase while
+  // processing the template URLs from the web data service.  In this case,
+  // GetTemplateURLForKeyword() will look not only at what's already in the
+  // model, but at the |initial_default_search_provider_|.  Since this engine
+  // will presumably also be present in the web data, we need to double-check
+  // that any "pre-existing" entries we find are actually coming from
+  // |template_urls_|, lest we detect a "conflict" between the
+  // |initial_default_search_provider_| and the web data version of itself.
+  if (existing_keyword_turl &&
+      (std::find(template_urls_.begin(), template_urls_.end(),
+                 existing_keyword_turl) != template_urls_.end())) {
+    DCHECK_NE(existing_keyword_turl, template_url);
+    // Only replace one of the TemplateURLs if they are either both extensions,
+    // or both not extensions.
+    bool are_same_type = existing_keyword_turl->GetType() ==
+        template_url->GetType();
+    if (CanReplace(existing_keyword_turl) && are_same_type) {
+      RemoveNoNotify(existing_keyword_turl);
+    } else if (CanReplace(template_url) && are_same_type) {
+      delete template_url;
+      return false;
+    } else {
+      base::string16 new_keyword =
+          UniquifyKeyword(*existing_keyword_turl, false);
+      ResetTemplateURLNoNotify(existing_keyword_turl,
+                               existing_keyword_turl->short_name(), new_keyword,
+                               existing_keyword_turl->url());
+    }
+  }
+  template_urls_.push_back(template_url);
+  AddToMaps(template_url);
+
+  if (newly_adding &&
+      (template_url->GetType() !=
+          TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION)) {
+    if (web_data_service_)
+      web_data_service_->AddKeyword(template_url->data());
+
+    // Inform sync of the addition. Note that this will assign a GUID to
+    // template_url and add it to the guid_to_template_map_.
+    ProcessTemplateURLChange(FROM_HERE,
+                             template_url,
+                             syncer::SyncChange::ACTION_ADD);
+  }
+
+  return true;
+}
+
+void TemplateURLService::RemoveNoNotify(TemplateURL* template_url) {
+  DCHECK(template_url != default_search_provider_);
+
+  TemplateURLVector::iterator i =
+      std::find(template_urls_.begin(), template_urls_.end(), template_url);
+  if (i == template_urls_.end())
+    return;
+
+  RemoveFromMaps(template_url);
+
+  // Remove it from the vector containing all TemplateURLs.
+  template_urls_.erase(i);
+
+  if (template_url->GetType() != TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION) {
+    if (web_data_service_)
+      web_data_service_->RemoveKeyword(template_url->id());
+
+    // Inform sync of the deletion.
+    ProcessTemplateURLChange(FROM_HERE,
+                             template_url,
+                             syncer::SyncChange::ACTION_DELETE);
+
+    UMA_HISTOGRAM_ENUMERATION(kDeleteSyncedEngineHistogramName,
+                              DELETE_ENGINE_USER_ACTION, DELETE_ENGINE_MAX);
+  }
+
+  if (loaded_ && client_)
+    client_->DeleteAllSearchTermsForKeyword(template_url->id());
+
+  // We own the TemplateURL and need to delete it.
+  delete template_url;
+}
+
+bool TemplateURLService::ResetTemplateURLNoNotify(
+    TemplateURL* url,
+    const base::string16& title,
+    const base::string16& keyword,
+    const std::string& search_url) {
+  DCHECK(!keyword.empty());
+  DCHECK(!search_url.empty());
+  TemplateURLData data(url->data());
+  data.short_name = title;
+  data.SetKeyword(keyword);
+  if (search_url != data.url()) {
+    data.SetURL(search_url);
+    // The urls have changed, reset the favicon url.
+    data.favicon_url = GURL();
+  }
+  data.safe_for_autoreplace = false;
+  data.last_modified = time_provider_();
+  return UpdateNoNotify(url, TemplateURL(data));
+}
+
+void TemplateURLService::NotifyObservers() {
+  if (!loaded_)
+    return;
+
+  FOR_EACH_OBSERVER(TemplateURLServiceObserver, model_observers_,
+                    OnTemplateURLServiceChanged());
+}
+
+// |template_urls| are the TemplateURLs loaded from the database.
+// |default_from_prefs| is the default search provider from the preferences, or
+// NULL if the DSE is not policy-defined.
+//
+// This function removes from the vector and the database all the TemplateURLs
+// that were set by policy, unless it is the current default search provider, in
+// which case it is updated with the data from prefs.
+void TemplateURLService::UpdateProvidersCreatedByPolicy(
+    TemplateURLVector* template_urls,
+    const TemplateURLData* default_from_prefs) {
+  DCHECK(template_urls);
+
+  for (TemplateURLVector::iterator i = template_urls->begin();
+       i != template_urls->end(); ) {
+    TemplateURL* template_url = *i;
+    if (template_url->created_by_policy()) {
+      if (default_from_prefs &&
+          TemplateURL::MatchesData(template_url, default_from_prefs,
+                                   search_terms_data())) {
+        // If the database specified a default search provider that was set
+        // by policy, and the default search provider from the preferences
+        // is also set by policy and they are the same, keep the entry in the
+        // database and the |default_search_provider|.
+        default_search_provider_ = template_url;
+        // Prevent us from saving any other entries, or creating a new one.
+        default_from_prefs = NULL;
+        ++i;
+        continue;
+      }
+
+      RemoveFromMaps(template_url);
+      i = template_urls->erase(i);
+      if (web_data_service_)
+        web_data_service_->RemoveKeyword(template_url->id());
+      delete template_url;
+    } else {
+      ++i;
+    }
+  }
+
+  if (default_from_prefs) {
+    default_search_provider_ = NULL;
+    default_search_provider_source_ = DefaultSearchManager::FROM_POLICY;
+    TemplateURLData new_data(*default_from_prefs);
+    if (new_data.sync_guid.empty())
+      new_data.sync_guid = base::GenerateGUID();
+    new_data.created_by_policy = true;
+    TemplateURL* new_dse = new TemplateURL(new_data);
+    if (AddNoNotify(new_dse, true))
+      default_search_provider_ = new_dse;
+  }
+}
+
+void TemplateURLService::ResetTemplateURLGUID(TemplateURL* url,
+                                              const std::string& guid) {
+  DCHECK(loaded_);
+  DCHECK(!guid.empty());
+
+  TemplateURLData data(url->data());
+  data.sync_guid = guid;
+  UpdateNoNotify(url, TemplateURL(data));
+}
+
+base::string16 TemplateURLService::UniquifyKeyword(const TemplateURL& turl,
+                                                   bool force) {
+  if (!force) {
+    // Already unique.
+    if (!GetTemplateURLForKeyword(turl.keyword()))
+      return turl.keyword();
+
+    // First, try to return the generated keyword for the TemplateURL (except
+    // for extensions, as their keywords are not associated with their URLs).
+    GURL gurl(turl.url());
+    if (gurl.is_valid() &&
+        (turl.GetType() != TemplateURL::OMNIBOX_API_EXTENSION)) {
+      base::string16 keyword_candidate = TemplateURL::GenerateKeyword(gurl);
+      if (!GetTemplateURLForKeyword(keyword_candidate))
+        return keyword_candidate;
+    }
+  }
+
+  // We try to uniquify the keyword by appending a special character to the end.
+  // This is a best-effort approach where we try to preserve the original
+  // keyword and let the user do what they will after our attempt.
+  base::string16 keyword_candidate(turl.keyword());
+  do {
+    keyword_candidate.append(base::ASCIIToUTF16("_"));
+  } while (GetTemplateURLForKeyword(keyword_candidate));
+
+  return keyword_candidate;
+}
+
+bool TemplateURLService::IsLocalTemplateURLBetter(
+    const TemplateURL* local_turl,
+    const TemplateURL* sync_turl) {
+  DCHECK(GetTemplateURLForGUID(local_turl->sync_guid()));
+  return local_turl->last_modified() > sync_turl->last_modified() ||
+         local_turl->created_by_policy() ||
+         local_turl== GetDefaultSearchProvider();
+}
+
+void TemplateURLService::ResolveSyncKeywordConflict(
+    TemplateURL* unapplied_sync_turl,
+    TemplateURL* applied_sync_turl,
+    syncer::SyncChangeList* change_list) {
+  DCHECK(loaded_);
+  DCHECK(unapplied_sync_turl);
+  DCHECK(applied_sync_turl);
+  DCHECK(change_list);
+  DCHECK_EQ(applied_sync_turl->keyword(), unapplied_sync_turl->keyword());
+  DCHECK_NE(TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION,
+            applied_sync_turl->GetType());
+
+  // Both |unapplied_sync_turl| and |applied_sync_turl| are known to Sync, so
+  // don't delete either of them. Instead, determine which is "better" and
+  // uniquify the other one, sending an update to the server for the updated
+  // entry.
+  const bool applied_turl_is_better =
+      IsLocalTemplateURLBetter(applied_sync_turl, unapplied_sync_turl);
+  TemplateURL* loser = applied_turl_is_better ?
+      unapplied_sync_turl : applied_sync_turl;
+  base::string16 new_keyword = UniquifyKeyword(*loser, false);
+  DCHECK(!GetTemplateURLForKeyword(new_keyword));
+  if (applied_turl_is_better) {
+    // Just set the keyword of |unapplied_sync_turl|. The caller is responsible
+    // for adding or updating unapplied_sync_turl in the local model.
+    unapplied_sync_turl->data_.SetKeyword(new_keyword);
+  } else {
+    // Update |applied_sync_turl| in the local model with the new keyword.
+    TemplateURLData data(applied_sync_turl->data());
+    data.SetKeyword(new_keyword);
+    if (UpdateNoNotify(applied_sync_turl, TemplateURL(data)))
+      NotifyObservers();
+  }
+  // The losing TemplateURL should have their keyword updated. Send a change to
+  // the server to reflect this change.
+  syncer::SyncData sync_data = CreateSyncDataFromTemplateURL(*loser);
+  change_list->push_back(syncer::SyncChange(FROM_HERE,
+      syncer::SyncChange::ACTION_UPDATE,
+      sync_data));
+}
+
+void TemplateURLService::MergeInSyncTemplateURL(
+    TemplateURL* sync_turl,
+    const SyncDataMap& sync_data,
+    syncer::SyncChangeList* change_list,
+    SyncDataMap* local_data,
+    syncer::SyncMergeResult* merge_result) {
+  DCHECK(sync_turl);
+  DCHECK(!GetTemplateURLForGUID(sync_turl->sync_guid()));
+  DCHECK(IsFromSync(sync_turl, sync_data));
+
+  TemplateURL* conflicting_turl =
+      FindNonExtensionTemplateURLForKeyword(sync_turl->keyword());
+  bool should_add_sync_turl = true;
+
+  // If there was no TemplateURL in the local model that conflicts with
+  // |sync_turl|, skip the following preparation steps and just add |sync_turl|
+  // directly. Otherwise, modify |conflicting_turl| to make room for
+  // |sync_turl|.
+  if (conflicting_turl) {
+    if (IsFromSync(conflicting_turl, sync_data)) {
+      // |conflicting_turl| is already known to Sync, so we're not allowed to
+      // remove it. In this case, we want to uniquify the worse one and send an
+      // update for the changed keyword to sync. We can reuse the logic from
+      // ResolveSyncKeywordConflict for this.
+      ResolveSyncKeywordConflict(sync_turl, conflicting_turl, change_list);
+      merge_result->set_num_items_modified(
+          merge_result->num_items_modified() + 1);
+    } else {
+      // |conflicting_turl| is not yet known to Sync. If it is better, then we
+      // want to transfer its values up to sync. Otherwise, we remove it and
+      // allow the entry from Sync to overtake it in the model.
+      const std::string guid = conflicting_turl->sync_guid();
+      if (IsLocalTemplateURLBetter(conflicting_turl, sync_turl)) {
+        ResetTemplateURLGUID(conflicting_turl, sync_turl->sync_guid());
+        syncer::SyncData sync_data =
+            CreateSyncDataFromTemplateURL(*conflicting_turl);
+        change_list->push_back(syncer::SyncChange(
+            FROM_HERE, syncer::SyncChange::ACTION_UPDATE, sync_data));
+        // Note that in this case we do not add the Sync TemplateURL to the
+        // local model, since we've effectively "merged" it in by updating the
+        // local conflicting entry with its sync_guid.
+        should_add_sync_turl = false;
+        merge_result->set_num_items_modified(
+            merge_result->num_items_modified() + 1);
+      } else {
+        // We guarantee that this isn't the local search provider. Otherwise,
+        // local would have won.
+        DCHECK(conflicting_turl != GetDefaultSearchProvider());
+        Remove(conflicting_turl);
+        merge_result->set_num_items_deleted(
+            merge_result->num_items_deleted() + 1);
+      }
+      // This TemplateURL was either removed or overwritten in the local model.
+      // Remove the entry from the local data so it isn't pushed up to Sync.
+      local_data->erase(guid);
+    }
+  }
+
+  if (should_add_sync_turl) {
+    // Force the local ID to kInvalidTemplateURLID so we can add it.
+    TemplateURLData data(sync_turl->data());
+    data.id = kInvalidTemplateURLID;
+    TemplateURL* added = new TemplateURL(data);
+    base::AutoReset<DefaultSearchChangeOrigin> change_origin(
+        &dsp_change_origin_, DSP_CHANGE_SYNC_ADD);
+    if (Add(added))
+      MaybeUpdateDSEAfterSync(added);
+    merge_result->set_num_items_added(
+        merge_result->num_items_added() + 1);
+  }
+}
+
+void TemplateURLService::PatchMissingSyncGUIDs(
+    TemplateURLVector* template_urls) {
+  DCHECK(template_urls);
+  for (TemplateURLVector::iterator i = template_urls->begin();
+       i != template_urls->end(); ++i) {
+    TemplateURL* template_url = *i;
+    DCHECK(template_url);
+    if (template_url->sync_guid().empty() &&
+        (template_url->GetType() !=
+            TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION)) {
+      template_url->data_.sync_guid = base::GenerateGUID();
+      if (web_data_service_)
+        web_data_service_->UpdateKeyword(template_url->data());
+    }
+  }
+}
+
+void TemplateURLService::OnSyncedDefaultSearchProviderGUIDChanged() {
+  base::AutoReset<DefaultSearchChangeOrigin> change_origin(
+      &dsp_change_origin_, DSP_CHANGE_SYNC_PREF);
+
+  std::string new_guid =
+      prefs_->GetString(prefs::kSyncedDefaultSearchProviderGUID);
+  if (new_guid.empty()) {
+    default_search_manager_.ClearUserSelectedDefaultSearchEngine();
+    return;
+  }
+
+  TemplateURL* turl = GetTemplateURLForGUID(new_guid);
+  if (turl)
+    default_search_manager_.SetUserSelectedDefaultSearchEngine(turl->data());
+}
+
+TemplateURL* TemplateURLService::FindPrepopulatedTemplateURL(
+    int prepopulated_id) {
+  for (TemplateURLVector::const_iterator i = template_urls_.begin();
+       i != template_urls_.end(); ++i) {
+    if ((*i)->prepopulate_id() == prepopulated_id)
+      return *i;
+  }
+  return NULL;
+}
+
+TemplateURL* TemplateURLService::FindTemplateURLForExtension(
+    const std::string& extension_id,
+    TemplateURL::Type type) {
+  DCHECK_NE(TemplateURL::NORMAL, type);
+  for (TemplateURLVector::const_iterator i = template_urls_.begin();
+       i != template_urls_.end(); ++i) {
+    if ((*i)->GetType() == type &&
+        (*i)->GetExtensionId() == extension_id)
+      return *i;
+  }
+  return NULL;
+}
+
+TemplateURL* TemplateURLService::FindMatchingExtensionTemplateURL(
+    const TemplateURLData& data,
+    TemplateURL::Type type) {
+  DCHECK_NE(TemplateURL::NORMAL, type);
+  for (TemplateURLVector::const_iterator i = template_urls_.begin();
+       i != template_urls_.end(); ++i) {
+    if ((*i)->GetType() == type &&
+        TemplateURL::MatchesData(*i, &data, search_terms_data()))
+      return *i;
+  }
+  return NULL;
+}
+
+void TemplateURLService::UpdateExtensionDefaultSearchEngine() {
+  TemplateURL* most_recently_intalled_default = NULL;
+  for (TemplateURLVector::const_iterator i = template_urls_.begin();
+       i != template_urls_.end(); ++i) {
+    if (((*i)->GetType() == TemplateURL::NORMAL_CONTROLLED_BY_EXTENSION) &&
+        (*i)->extension_info_->wants_to_be_default_engine &&
+        (*i)->SupportsReplacement(search_terms_data()) &&
+        (!most_recently_intalled_default ||
+         (most_recently_intalled_default->extension_info_->install_time <
+             (*i)->extension_info_->install_time)))
+      most_recently_intalled_default = *i;
+  }
+
+  if (most_recently_intalled_default) {
+    base::AutoReset<DefaultSearchChangeOrigin> change_origin(
+        &dsp_change_origin_, DSP_CHANGE_OVERRIDE_SETTINGS_EXTENSION);
+    default_search_manager_.SetExtensionControlledDefaultSearchEngine(
+        most_recently_intalled_default->data());
+  } else {
+    default_search_manager_.ClearExtensionControlledDefaultSearchEngine();
+  }
+}