Remove some unused history resources on iOS

ios/chrome/browser/ui/webui/history/browsing_history_handler.cc

Index: ios/chrome/browser/ui/webui/history/browsing_history_handler.cc
diff --git a/ios/chrome/browser/ui/webui/history/browsing_history_handler.cc b/ios/chrome/browser/ui/webui/history/browsing_history_handler.cc
deleted file mode 100644
index dbf8d2b6a4873106001dae80742d0f84a03fcd79..0000000000000000000000000000000000000000
--- a/ios/chrome/browser/ui/webui/history/browsing_history_handler.cc
+++ /dev/null
@@ -1,860 +0,0 @@
-// Copyright 2016 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 "ios/chrome/browser/ui/webui/history/browsing_history_handler.h"
-
-#include <stddef.h>
-
-#include <set>
-
-#include "base/bind.h"
-#include "base/bind_helpers.h"
-#include "base/i18n/rtl.h"
-#include "base/i18n/time_formatting.h"
-#include "base/metrics/histogram.h"
-#include "base/strings/string16.h"
-#include "base/strings/string_number_conversions.h"
-#include "base/strings/utf_string_conversions.h"
-#include "base/time/time.h"
-#include "base/values.h"
-#include "components/bookmarks/browser/bookmark_model.h"
-#include "components/bookmarks/browser/bookmark_utils.h"
-#include "components/browser_sync/profile_sync_service.h"
-#include "components/browsing_data/core/history_notice_utils.h"
-#include "components/history/core/browser/history_service.h"
-#include "components/history/core/browser/history_types.h"
-#include "components/history/core/browser/top_sites.h"
-#include "components/history/core/browser/web_history_service.h"
-#include "components/keyed_service/core/service_access_type.h"
-#include "components/strings/grit/components_strings.h"
-#include "components/sync/device_info/device_info.h"
-#include "components/sync/device_info/device_info_tracker.h"
-#include "components/sync/protocol/history_delete_directive_specifics.pb.h"
-#include "components/sync/protocol/sync_enums.pb.h"
-#include "components/url_formatter/url_formatter.h"
-#include "ios/chrome/browser/bookmarks/bookmark_model_factory.h"
-#include "ios/chrome/browser/browser_state/chrome_browser_state.h"
-#include "ios/chrome/browser/chrome_url_constants.h"
-#include "ios/chrome/browser/favicon/favicon_service_factory.h"
-#include "ios/chrome/browser/history/history_service_factory.h"
-#include "ios/chrome/browser/history/history_utils.h"
-#include "ios/chrome/browser/history/top_sites_factory.h"
-#include "ios/chrome/browser/history/web_history_service_factory.h"
-#include "ios/chrome/browser/sync/ios_chrome_profile_sync_service_factory.h"
-#include "ios/chrome/browser/ui/show_privacy_settings_util.h"
-#include "ios/chrome/browser/ui/webui/history/favicon_source.h"
-#include "ios/web/public/url_data_source_ios.h"
-#include "ios/web/public/webui/web_ui_ios.h"
-#include "ui/base/l10n/l10n_util.h"
-#include "ui/base/l10n/time_format.h"
-
-// The amount of time to wait for a response from the WebHistoryService.
-static const int kWebHistoryTimeoutSeconds = 3;
-
-using bookmarks::BookmarkModel;
-
-namespace {
-
-// Buckets for UMA histograms.
-enum WebHistoryQueryBuckets {
-  WEB_HISTORY_QUERY_FAILED = 0,
-  WEB_HISTORY_QUERY_SUCCEEDED,
-  WEB_HISTORY_QUERY_TIMED_OUT,
-  NUM_WEB_HISTORY_QUERY_BUCKETS
-};
-
-// Identifiers for the type of device from which a history entry originated.
-static const char kDeviceTypeLaptop[] = "laptop";
-static const char kDeviceTypePhone[] = "phone";
-static const char kDeviceTypeTablet[] = "tablet";
-
-// Returns a localized version of |visit_time| including a relative
-// indicator (e.g. today, yesterday).
-base::string16 GetRelativeDateLocalized(const base::Time& visit_time) {
-  base::Time midnight = base::Time::Now().LocalMidnight();
-  base::string16 date_str = ui::TimeFormat::RelativeDate(visit_time, &midnight);
-  if (date_str.empty()) {
-    date_str = base::TimeFormatFriendlyDate(visit_time);
-  } else {
-    date_str = l10n_util::GetStringFUTF16(
-        IDS_HISTORY_DATE_WITH_RELATIVE_TIME, date_str,
-        base::TimeFormatFriendlyDate(visit_time));
-  }
-  return date_str;
-}
-
-// Sets the correct year when substracting months from a date.
-void NormalizeMonths(base::Time::Exploded* exploded) {
-  // Decrease a year at a time until we have a proper date.
-  while (exploded->month < 1) {
-    exploded->month += 12;
-    exploded->year--;
-  }
-}
-
-// Returns true if |entry| represents a local visit that had no corresponding
-// visit on the server.
-bool IsLocalOnlyResult(const BrowsingHistoryHandler::HistoryEntry& entry) {
-  return entry.entry_type == BrowsingHistoryHandler::HistoryEntry::LOCAL_ENTRY;
-}
-
-// Gets the name and type of a device for the given sync client ID.
-// |name| and |type| are out parameters.
-void GetDeviceNameAndType(const browser_sync::ProfileSyncService* sync_service,
-                          const std::string& client_id,
-                          std::string* name,
-                          std::string* type) {
-  // DeviceInfoTracker must be syncing in order for remote history entries to
-  // be available.
-  DCHECK(sync_service);
-  DCHECK(sync_service->GetDeviceInfoTracker());
-  DCHECK(sync_service->GetDeviceInfoTracker()->IsSyncing());
-
-  std::unique_ptr<syncer::DeviceInfo> device_info =
-      sync_service->GetDeviceInfoTracker()->GetDeviceInfo(client_id);
-  if (device_info.get()) {
-    *name = device_info->client_name();
-    switch (device_info->device_type()) {
-      case sync_pb::SyncEnums::TYPE_PHONE:
-        *type = kDeviceTypePhone;
-        break;
-      case sync_pb::SyncEnums::TYPE_TABLET:
-        *type = kDeviceTypeTablet;
-        break;
-      default:
-        *type = kDeviceTypeLaptop;
-    }
-    return;
-  }
-
-  *name = l10n_util::GetStringUTF8(IDS_HISTORY_UNKNOWN_DEVICE);
-  *type = kDeviceTypeLaptop;
-}
-
-void RecordMetricsForNoticeAboutOtherFormsOfBrowsingHistory(bool shown) {
-  UMA_HISTOGRAM_BOOLEAN("History.ShownHeaderAboutOtherFormsOfBrowsingHistory",
-                        shown);
-}
-
-}  // namespace
-
-BrowsingHistoryHandler::HistoryEntry::HistoryEntry(
-    BrowsingHistoryHandler::HistoryEntry::EntryType entry_type,
-    const GURL& url,
-    const base::string16& title,
-    base::Time time,
-    const std::string& client_id,
-    bool is_search_result,
-    const base::string16& snippet,
-    bool blocked_visit) {
-  this->entry_type = entry_type;
-  this->url = url;
-  this->title = title;
-  this->time = time;
-  this->client_id = client_id;
-  all_timestamps.insert(time.ToInternalValue());
-  this->is_search_result = is_search_result;
-  this->snippet = snippet;
-  this->blocked_visit = blocked_visit;
-}
-
-BrowsingHistoryHandler::HistoryEntry::HistoryEntry()
-    : entry_type(EMPTY_ENTRY), is_search_result(false), blocked_visit(false) {}
-
-BrowsingHistoryHandler::HistoryEntry::HistoryEntry(const HistoryEntry& other) =
-    default;
-
-BrowsingHistoryHandler::HistoryEntry::~HistoryEntry() {}
-
-void BrowsingHistoryHandler::HistoryEntry::SetUrlAndTitle(
-    base::DictionaryValue* result) const {
-  result->SetString("url", url.spec());
-
-  bool using_url_as_the_title = false;
-  base::string16 title_to_set(title);
-  if (title.empty()) {
-    using_url_as_the_title = true;
-    title_to_set = base::UTF8ToUTF16(url.spec());
-  }
-
-  // Since the title can contain BiDi text, we need to mark the text as either
-  // RTL or LTR, depending on the characters in the string. If we use the URL
-  // as the title, we mark the title as LTR since URLs are always treated as
-  // left to right strings.
-  if (base::i18n::IsRTL()) {
-    if (using_url_as_the_title)
-      base::i18n::WrapStringWithLTRFormatting(&title_to_set);
-    else
-      base::i18n::AdjustStringForLocaleDirection(&title_to_set);
-  }
-  result->SetString("title", title_to_set);
-}
-
-std::unique_ptr<base::DictionaryValue>
-BrowsingHistoryHandler::HistoryEntry::ToValue(
-    BookmarkModel* bookmark_model,
-    SupervisedUserService* supervised_user_service,
-    const browser_sync::ProfileSyncService* sync_service) const {
-  std::unique_ptr<base::DictionaryValue> result(new base::DictionaryValue());
-  SetUrlAndTitle(result.get());
-
-  base::string16 domain = url_formatter::IDNToUnicode(url.host());
-  // When the domain is empty, use the scheme instead. This allows for a
-  // sensible treatment of e.g. file: URLs when group by domain is on.
-  if (domain.empty())
-    domain = base::UTF8ToUTF16(url.scheme() + ":");
-
-  // The items which are to be written into result are also described in
-  // chrome/browser/resources/history/history.js in @typedef for
-  // HistoryEntry. Please update it whenever you add or remove
-  // any keys in result.
-  result->SetString("domain", domain);
-  result->SetDouble("time", time.ToJsTime());
-
-  // Pass the timestamps in a list.
-  std::unique_ptr<base::ListValue> timestamps(new base::ListValue);
-  for (int64_t timestamp : all_timestamps) {
-    timestamps->AppendDouble(
-        base::Time::FromInternalValue(timestamp).ToJsTime());
-  }
-  result->Set("allTimestamps", timestamps.release());
-
-  // Always pass the short date since it is needed both in the search and in
-  // the monthly view.
-  result->SetString("dateShort", base::TimeFormatShortDate(time));
-
-  // Only pass in the strings we need (search results need a shortdate
-  // and snippet, browse results need day and time information).
-  if (is_search_result) {
-    result->SetString("snippet", snippet);
-  } else {
-    base::Time midnight = base::Time::Now().LocalMidnight();
-    base::string16 date_str = ui::TimeFormat::RelativeDate(time, &midnight);
-    if (date_str.empty()) {
-      date_str = base::TimeFormatFriendlyDate(time);
-    } else {
-      date_str = l10n_util::GetStringFUTF16(IDS_HISTORY_DATE_WITH_RELATIVE_TIME,
-                                            date_str,
-                                            base::TimeFormatFriendlyDate(time));
-    }
-    result->SetString("dateRelativeDay", date_str);
-    result->SetString("dateTimeOfDay", base::TimeFormatTimeOfDay(time));
-  }
-  result->SetBoolean("starred", bookmark_model->IsBookmarked(url));
-
-  std::string device_name;
-  std::string device_type;
-  if (!client_id.empty())
-    GetDeviceNameAndType(sync_service, client_id, &device_name, &device_type);
-  result->SetString("deviceName", device_name);
-  result->SetString("deviceType", device_type);
-
-  return result;
-}
-
-bool BrowsingHistoryHandler::HistoryEntry::SortByTimeDescending(
-    const BrowsingHistoryHandler::HistoryEntry& entry1,
-    const BrowsingHistoryHandler::HistoryEntry& entry2) {
-  return entry1.time > entry2.time;
-}
-
-BrowsingHistoryHandler::BrowsingHistoryHandler()
-    : has_pending_delete_request_(false),
-      history_service_observer_(this),
-      has_synced_results_(false),
-      has_other_forms_of_browsing_history_(false),
-      weak_factory_(this) {}
-
-BrowsingHistoryHandler::~BrowsingHistoryHandler() {
-  query_task_tracker_.TryCancelAll();
-  web_history_request_.reset();
-}
-
-void BrowsingHistoryHandler::RegisterMessages() {
-  // Create our favicon data source.
-  ios::ChromeBrowserState* browser_state =
-      ios::ChromeBrowserState::FromWebUIIOS(web_ui());
-  ios::ChromeBrowserState* original_browser_state =
-      browser_state->GetOriginalChromeBrowserState();
-  favicon::FaviconService* favicon_service =
-      ios::FaviconServiceFactory::GetForBrowserState(
-          original_browser_state, ServiceAccessType::EXPLICIT_ACCESS);
-  scoped_refptr<history::TopSites> top_sites =
-      ios::TopSitesFactory::GetForBrowserState(original_browser_state);
-  syncer::SyncService* sync_service =
-      IOSChromeProfileSyncServiceFactory::GetForBrowserState(
-          original_browser_state);
-  web::URLDataSourceIOS::Add(
-      browser_state,
-      new FaviconSource(favicon_service, top_sites, sync_service));
-
-  // Get notifications when history is cleared.
-  history::HistoryService* hs = ios::HistoryServiceFactory::GetForBrowserState(
-      browser_state, ServiceAccessType::EXPLICIT_ACCESS);
-  if (hs)
-    history_service_observer_.Add(hs);
-
-  web_ui()->RegisterMessageCallback(
-      "queryHistory", base::Bind(&BrowsingHistoryHandler::HandleQueryHistory,
-                                 base::Unretained(this)));
-  web_ui()->RegisterMessageCallback(
-      "removeVisits", base::Bind(&BrowsingHistoryHandler::HandleRemoveVisits,
-                                 base::Unretained(this)));
-  web_ui()->RegisterMessageCallback(
-      "clearBrowsingData",
-      base::Bind(&BrowsingHistoryHandler::HandleClearBrowsingData,
-                 base::Unretained(this)));
-  web_ui()->RegisterMessageCallback(
-      "removeBookmark",
-      base::Bind(&BrowsingHistoryHandler::HandleRemoveBookmark,
-                 base::Unretained(this)));
-}
-
-bool BrowsingHistoryHandler::ExtractIntegerValueAtIndex(
-    const base::ListValue* value,
-    int index,
-    int* out_int) {
-  double double_value;
-  if (value->GetDouble(index, &double_value)) {
-    *out_int = static_cast<int>(double_value);
-    return true;
-  }
-  NOTREACHED();
-  return false;
-}
-
-void BrowsingHistoryHandler::WebHistoryTimeout() {
-  // TODO(dubroy): Communicate the failure to the front end.
-  if (!query_task_tracker_.HasTrackedTasks())
-    ReturnResultsToFrontEnd();
-
-  UMA_HISTOGRAM_ENUMERATION("WebHistory.QueryCompletion",
-                            WEB_HISTORY_QUERY_TIMED_OUT,
-                            NUM_WEB_HISTORY_QUERY_BUCKETS);
-}
-
-void BrowsingHistoryHandler::QueryHistory(
-    const base::string16& search_text,
-    const history::QueryOptions& options) {
-  ios::ChromeBrowserState* browser_state =
-      ios::ChromeBrowserState::FromWebUIIOS(web_ui());
-
-  // Anything in-flight is invalid.
-  query_task_tracker_.TryCancelAll();
-  web_history_request_.reset();
-
-  query_results_.clear();
-  results_info_value_.Clear();
-  has_synced_results_ = false;
-  has_other_forms_of_browsing_history_ = false;
-
-  history::HistoryService* hs = ios::HistoryServiceFactory::GetForBrowserState(
-      browser_state, ServiceAccessType::EXPLICIT_ACCESS);
-  hs->QueryHistory(search_text, options,
-                   base::Bind(&BrowsingHistoryHandler::QueryComplete,
-                              base::Unretained(this), search_text, options),
-                   &query_task_tracker_);
-
-  history::WebHistoryService* web_history =
-      ios::WebHistoryServiceFactory::GetForBrowserState(browser_state);
-  if (web_history) {
-    web_history_query_results_.clear();
-    web_history_request_ = web_history->QueryHistory(
-        search_text, options,
-        base::Bind(&BrowsingHistoryHandler::WebHistoryQueryComplete,
-                   base::Unretained(this), search_text, options,
-                   base::TimeTicks::Now()));
-    // Start a timer so we know when to give up.
-    web_history_timer_.Start(
-        FROM_HERE, base::TimeDelta::FromSeconds(kWebHistoryTimeoutSeconds),
-        this, &BrowsingHistoryHandler::WebHistoryTimeout);
-
-    browser_sync::ProfileSyncService* sync_service =
-        IOSChromeProfileSyncServiceFactory::GetInstance()->GetForBrowserState(
-            browser_state);
-    // Test the existence of other forms of browsing history.
-    browsing_data::ShouldShowNoticeAboutOtherFormsOfBrowsingHistory(
-        sync_service, web_history,
-        base::Bind(
-            &BrowsingHistoryHandler::OtherFormsOfBrowsingHistoryQueryComplete,
-            weak_factory_.GetWeakPtr()));
-
-    // Set this to false until the results actually arrive.
-    results_info_value_.SetBoolean("hasSyncedResults", false);
-  } else {
-    // The notice could not have been shown, because there is no web history.
-    RecordMetricsForNoticeAboutOtherFormsOfBrowsingHistory(false);
-  }
-}
-
-void BrowsingHistoryHandler::HandleQueryHistory(const base::ListValue* args) {
-  history::QueryOptions options;
-
-  // Parse the arguments from JavaScript. There are five required arguments:
-  // - the text to search for (may be empty)
-  // - the offset from which the search should start (in multiples of week or
-  //   month, set by the next argument).
-  // - the range (BrowsingHistoryHandler::Range) Enum value that sets the range
-  //   of the query.
-  // - the end time for the query. Only results older than this time will be
-  //   returned.
-  // - the maximum number of results to return (may be 0, meaning that there
-  //   is no maximum).
-  base::string16 search_text = ExtractStringValue(args);
-  int offset;
-  if (!args->GetInteger(1, &offset)) {
-    NOTREACHED() << "Failed to convert argument 1. ";
-    return;
-  }
-  int range;
-  if (!args->GetInteger(2, &range)) {
-    NOTREACHED() << "Failed to convert argument 2. ";
-    return;
-  }
-
-  if (range == BrowsingHistoryHandler::MONTH)
-    SetQueryTimeInMonths(offset, &options);
-  else if (range == BrowsingHistoryHandler::WEEK)
-    SetQueryTimeInWeeks(offset, &options);
-
-  double end_time;
-  if (!args->GetDouble(3, &end_time)) {
-    NOTREACHED() << "Failed to convert argument 3. ";
-    return;
-  }
-  if (end_time)
-    options.end_time = base::Time::FromJsTime(end_time);
-
-  if (!ExtractIntegerValueAtIndex(args, 4, &options.max_count)) {
-    NOTREACHED() << "Failed to convert argument 4.";
-    return;
-  }
-
-  options.duplicate_policy = history::QueryOptions::REMOVE_DUPLICATES_PER_DAY;
-  QueryHistory(search_text, options);
-}
-
-void BrowsingHistoryHandler::HandleRemoveVisits(const base::ListValue* args) {
-  ios::ChromeBrowserState* browser_state =
-      ios::ChromeBrowserState::FromWebUIIOS(web_ui());
-  // TODO(davidben): history.js is not aware of this failure and will still
-  // override |deleteCompleteCallback_|.
-  if (delete_task_tracker_.HasTrackedTasks() || has_pending_delete_request_) {
-    web_ui()->CallJavascriptFunction("deleteFailed");
-    return;
-  }
-
-  history::HistoryService* history_service =
-      ios::HistoryServiceFactory::GetForBrowserState(
-          browser_state, ServiceAccessType::EXPLICIT_ACCESS);
-  history::WebHistoryService* web_history =
-      ios::WebHistoryServiceFactory::GetForBrowserState(browser_state);
-
-  base::Time now = base::Time::Now();
-  std::vector<history::ExpireHistoryArgs> expire_list;
-  expire_list.reserve(args->GetSize());
-
-  DCHECK(urls_to_be_deleted_.empty());
-  for (const auto& arg : *args) {
-    base::DictionaryValue* deletion = NULL;
-    base::string16 url;
-    base::ListValue* timestamps = NULL;
-
-    // Each argument is a dictionary with properties "url" and "timestamps".
-    if (!(arg->GetAsDictionary(&deletion) && deletion->GetString("url", &url) &&
-          deletion->GetList("timestamps", &timestamps))) {
-      NOTREACHED() << "Unable to extract arguments";
-      return;
-    }
-    DCHECK(timestamps->GetSize() > 0);
-
-    // In order to ensure that visits will be deleted from the server and other
-    // clients (even if they are offline), create a sync delete directive for
-    // each visit to be deleted.
-    sync_pb::HistoryDeleteDirectiveSpecifics delete_directive;
-    sync_pb::GlobalIdDirective* global_id_directive =
-        delete_directive.mutable_global_id_directive();
-
-    double timestamp;
-    history::ExpireHistoryArgs* expire_args = NULL;
-    for (const auto& timestamp_value : *timestamps) {
-      if (!timestamp_value->GetAsDouble(&timestamp)) {
-        NOTREACHED() << "Unable to extract visit timestamp.";
-        continue;
-      }
-      base::Time visit_time = base::Time::FromJsTime(timestamp);
-      if (!expire_args) {
-        GURL gurl(url);
-        expire_list.resize(expire_list.size() + 1);
-        expire_args = &expire_list.back();
-        expire_args->SetTimeRangeForOneDay(visit_time);
-        expire_args->urls.insert(gurl);
-        urls_to_be_deleted_.insert(gurl);
-      }
-      // The local visit time is treated as a global ID for the visit.
-      global_id_directive->add_global_id(visit_time.ToInternalValue());
-    }
-
-    // Set the start and end time in microseconds since the Unix epoch.
-    global_id_directive->set_start_time_usec(
-        (expire_args->begin_time - base::Time::UnixEpoch()).InMicroseconds());
-
-    // Delete directives shouldn't have an end time in the future.
-    // TODO(dubroy): Use sane time (crbug.com/146090) here when it's ready.
-    base::Time end_time = std::min(expire_args->end_time, now);
-
-    // -1 because end time in delete directives is inclusive.
-    global_id_directive->set_end_time_usec(
-        (end_time - base::Time::UnixEpoch()).InMicroseconds() - 1);
-
-    // TODO(dubroy): Figure out the proper way to handle an error here.
-    if (web_history)
-      history_service->ProcessLocalDeleteDirective(delete_directive);
-  }
-
-  history_service->ExpireHistory(
-      expire_list, base::Bind(&BrowsingHistoryHandler::RemoveComplete,
-                              base::Unretained(this)),
-      &delete_task_tracker_);
-
-  if (web_history) {
-    has_pending_delete_request_ = true;
-    web_history->ExpireHistory(
-        expire_list,
-        base::Bind(&BrowsingHistoryHandler::RemoveWebHistoryComplete,
-                   weak_factory_.GetWeakPtr()));
-  }
-}
-
-void BrowsingHistoryHandler::HandleClearBrowsingData(
-    const base::ListValue* args) {
-  ShowClearBrowsingData();
-}
-
-void BrowsingHistoryHandler::HandleRemoveBookmark(const base::ListValue* args) {
-  base::string16 url = ExtractStringValue(args);
-  ios::ChromeBrowserState* browser_state =
-      ios::ChromeBrowserState::FromWebUIIOS(web_ui());
-  BookmarkModel* model =
-      ios::BookmarkModelFactory::GetForBrowserState(browser_state);
-  bookmarks::RemoveAllBookmarks(model, GURL(url));
-}
-
-// static
-void BrowsingHistoryHandler::MergeDuplicateResults(
-    std::vector<BrowsingHistoryHandler::HistoryEntry>* results) {
-  std::vector<BrowsingHistoryHandler::HistoryEntry> new_results;
-  // Pre-reserve the size of the new vector. Since we're working with pointers
-  // later on not doing this could lead to the vector being resized and to
-  // pointers to invalid locations.
-  new_results.reserve(results->size());
-  // Maps a URL to the most recent entry on a particular day.
-  std::map<GURL, BrowsingHistoryHandler::HistoryEntry*> current_day_entries;
-
-  // Keeps track of the day that |current_day_urls| is holding the URLs for,
-  // in order to handle removing per-day duplicates.
-  base::Time current_day_midnight;
-
-  std::sort(results->begin(), results->end(),
-            HistoryEntry::SortByTimeDescending);
-
-  for (const BrowsingHistoryHandler::HistoryEntry& entry : *results) {
-    // Reset the list of found URLs when a visit from a new day is encountered.
-    if (current_day_midnight != entry.time.LocalMidnight()) {
-      current_day_entries.clear();
-      current_day_midnight = entry.time.LocalMidnight();
-    }
-
-    // Keep this visit if it's the first visit to this URL on the current day.
-    if (current_day_entries.count(entry.url) == 0) {
-      new_results.push_back(entry);
-      current_day_entries[entry.url] = &new_results.back();
-    } else {
-      // Keep track of the timestamps of all visits to the URL on the same day.
-      BrowsingHistoryHandler::HistoryEntry* combined_entry =
-          current_day_entries[entry.url];
-      combined_entry->all_timestamps.insert(entry.all_timestamps.begin(),
-                                            entry.all_timestamps.end());
-
-      if (combined_entry->entry_type != entry.entry_type) {
-        combined_entry->entry_type =
-            BrowsingHistoryHandler::HistoryEntry::COMBINED_ENTRY;
-      }
-    }
-  }
-  results->swap(new_results);
-}
-
-void BrowsingHistoryHandler::ReturnResultsToFrontEnd() {
-  ios::ChromeBrowserState* browser_state =
-      ios::ChromeBrowserState::FromWebUIIOS(web_ui());
-  BookmarkModel* bookmark_model =
-      ios::BookmarkModelFactory::GetForBrowserState(browser_state);
-  browser_sync::ProfileSyncService* sync_service =
-      IOSChromeProfileSyncServiceFactory::GetForBrowserState(browser_state);
-
-  // Combine the local and remote results into |query_results_|, and remove
-  // any duplicates.
-  if (!web_history_query_results_.empty()) {
-    int local_result_count = query_results_.size();
-    query_results_.insert(query_results_.end(),
-                          web_history_query_results_.begin(),
-                          web_history_query_results_.end());
-    MergeDuplicateResults(&query_results_);
-
-    if (local_result_count) {
-      // In the best case, we expect that all local results are duplicated on
-      // the server. Keep track of how many are missing.
-      int missing_count = std::count_if(
-          query_results_.begin(), query_results_.end(), IsLocalOnlyResult);
-      UMA_HISTOGRAM_PERCENTAGE("WebHistory.LocalResultMissingOnServer",
-                               missing_count * 100.0 / local_result_count);
-    }
-  }
-
-  // Convert the result vector into a ListValue.
-  base::ListValue results_value;
-  for (const BrowsingHistoryHandler::HistoryEntry& entry : query_results_) {
-    std::unique_ptr<base::Value> value(
-        entry.ToValue(bookmark_model, nullptr, sync_service));
-    results_value.Append(value.release());
-  }
-
-  web_ui()->CallJavascriptFunction("historyResult", results_info_value_,
-                                   results_value);
-  web_ui()->CallJavascriptFunction(
-      "showNotification", base::FundamentalValue(has_synced_results_),
-      base::FundamentalValue(has_other_forms_of_browsing_history_));
-  results_info_value_.Clear();
-  query_results_.clear();
-  web_history_query_results_.clear();
-}
-
-void BrowsingHistoryHandler::QueryComplete(const base::string16& search_text,
-                                           const history::QueryOptions& options,
-                                           history::QueryResults* results) {
-  DCHECK_EQ(0U, query_results_.size());
-  query_results_.reserve(results->size());
-
-  for (size_t i = 0; i < results->size(); ++i) {
-    history::URLResult const& page = (*results)[i];
-    // TODO(dubroy): Use sane time (crbug.com/146090) here when it's ready.
-    query_results_.push_back(
-        HistoryEntry(HistoryEntry::LOCAL_ENTRY, page.url(), page.title(),
-                     page.visit_time(), std::string(), !search_text.empty(),
-                     page.snippet().text(), page.blocked_visit()));
-  }
-
-  // The items which are to be written into results_info_value_ are also
-  // described in chrome/browser/resources/history/history.js in @typedef for
-  // HistoryQuery. Please update it whenever you add or remove any keys in
-  // results_info_value_.
-  results_info_value_.SetString("term", search_text);
-  results_info_value_.SetBoolean("finished", results->reached_beginning());
-
-  // Add the specific dates that were searched to display them.
-  // TODO(sergiu): Put today if the start is in the future.
-  results_info_value_.SetString("queryStartTime",
-                                GetRelativeDateLocalized(options.begin_time));
-  if (!options.end_time.is_null()) {
-    results_info_value_.SetString(
-        "queryEndTime", GetRelativeDateLocalized(options.end_time -
-                                                 base::TimeDelta::FromDays(1)));
-  } else {
-    results_info_value_.SetString("queryEndTime",
-                                  GetRelativeDateLocalized(base::Time::Now()));
-  }
-  if (!web_history_timer_.IsRunning())
-    ReturnResultsToFrontEnd();
-}
-
-void BrowsingHistoryHandler::WebHistoryQueryComplete(
-    const base::string16& search_text,
-    const history::QueryOptions& options,
-    base::TimeTicks start_time,
-    history::WebHistoryService::Request* request,
-    const base::DictionaryValue* results_value) {
-  base::TimeDelta delta = base::TimeTicks::Now() - start_time;
-  UMA_HISTOGRAM_TIMES("WebHistory.ResponseTime", delta);
-
-  // If the response came in too late, do nothing.
-  // TODO(dubroy): Maybe show a banner, and prompt the user to reload?
-  if (!web_history_timer_.IsRunning())
-    return;
-  web_history_timer_.Stop();
-
-  UMA_HISTOGRAM_ENUMERATION(
-      "WebHistory.QueryCompletion",
-      results_value ? WEB_HISTORY_QUERY_SUCCEEDED : WEB_HISTORY_QUERY_FAILED,
-      NUM_WEB_HISTORY_QUERY_BUCKETS);
-
-  DCHECK_EQ(0U, web_history_query_results_.size());
-  const base::ListValue* events = NULL;
-  if (results_value && results_value->GetList("event", &events)) {
-    web_history_query_results_.reserve(events->GetSize());
-    for (unsigned int i = 0; i < events->GetSize(); ++i) {
-      const base::DictionaryValue* event = NULL;
-      const base::DictionaryValue* result = NULL;
-      const base::ListValue* results = NULL;
-      const base::ListValue* ids = NULL;
-      base::string16 url;
-      base::string16 title;
-      base::Time visit_time;
-
-      if (!(events->GetDictionary(i, &event) &&
-            event->GetList("result", &results) &&
-            results->GetDictionary(0, &result) &&
-            result->GetString("url", &url) && result->GetList("id", &ids) &&
-            ids->GetSize() > 0)) {
-        LOG(WARNING) << "Improperly formed JSON response from history server.";
-        continue;
-      }
-
-      // Ignore any URLs that should not be shown in the history page.
-      GURL gurl(url);
-      if (!ios::CanAddURLToHistory(gurl))
-        continue;
-
-      // Title is optional, so the return value is ignored here.
-      result->GetString("title", &title);
-
-      // Extract the timestamps of all the visits to this URL.
-      // They are referred to as "IDs" by the server.
-      for (int j = 0; j < static_cast<int>(ids->GetSize()); ++j) {
-        const base::DictionaryValue* id = NULL;
-        std::string timestamp_string;
-        int64_t timestamp_usec = 0;
-
-        if (!ids->GetDictionary(j, &id) ||
-            !id->GetString("timestamp_usec", &timestamp_string) ||
-            !base::StringToInt64(timestamp_string, &timestamp_usec)) {
-          NOTREACHED() << "Unable to extract timestamp.";
-          continue;
-        }
-        // The timestamp on the server is a Unix time.
-        base::Time time = base::Time::UnixEpoch() +
-                          base::TimeDelta::FromMicroseconds(timestamp_usec);
-
-        // Get the ID of the client that this visit came from.
-        std::string client_id;
-        id->GetString("client_id", &client_id);
-
-        web_history_query_results_.push_back(
-            HistoryEntry(HistoryEntry::REMOTE_ENTRY, gurl, title, time,
-                         client_id, !search_text.empty(), base::string16(),
-                         /* blocked_visit */ false));
-      }
-    }
-  }
-  has_synced_results_ = results_value != nullptr;
-  results_info_value_.SetBoolean("hasSyncedResults", has_synced_results_);
-  if (!query_task_tracker_.HasTrackedTasks())
-    ReturnResultsToFrontEnd();
-}
-
-void BrowsingHistoryHandler::OtherFormsOfBrowsingHistoryQueryComplete(
-    bool found_other_forms_of_browsing_history) {
-  has_other_forms_of_browsing_history_ = found_other_forms_of_browsing_history;
-  RecordMetricsForNoticeAboutOtherFormsOfBrowsingHistory(
-      has_other_forms_of_browsing_history_);
-  web_ui()->CallJavascriptFunction(
-      "showNotification", base::FundamentalValue(has_synced_results_),
-      base::FundamentalValue(has_other_forms_of_browsing_history_));
-}
-
-void BrowsingHistoryHandler::RemoveComplete() {
-  urls_to_be_deleted_.clear();
-
-  // Notify the page that the deletion request is complete, but only if a web
-  // history delete request is not still pending.
-  if (!has_pending_delete_request_)
-    web_ui()->CallJavascriptFunction("deleteComplete");
-}
-
-void BrowsingHistoryHandler::RemoveWebHistoryComplete(bool success) {
-  has_pending_delete_request_ = false;
-  // TODO(dubroy): Should we handle failure somehow? Delete directives will
-  // ensure that the visits are eventually deleted, so maybe it's not necessary.
-  if (!delete_task_tracker_.HasTrackedTasks())
-    RemoveComplete();
-}
-
-void BrowsingHistoryHandler::SetQueryTimeInWeeks(
-    int offset,
-    history::QueryOptions* options) {
-  // LocalMidnight returns the beginning of the current day so get the
-  // beginning of the next one.
-  base::Time midnight =
-      base::Time::Now().LocalMidnight() + base::TimeDelta::FromDays(1);
-  options->end_time = midnight - base::TimeDelta::FromDays(7 * offset);
-  options->begin_time = midnight - base::TimeDelta::FromDays(7 * (offset + 1));
-}
-
-void BrowsingHistoryHandler::SetQueryTimeInMonths(
-    int offset,
-    history::QueryOptions* options) {
-  // Configure the begin point of the search to the start of the
-  // current month.
-  base::Time::Exploded exploded;
-  base::Time::Now().LocalMidnight().LocalExplode(&exploded);
-  exploded.day_of_month = 1;
-
-  if (offset == 0) {
-    if (!base::Time::FromLocalExploded(exploded, &options->begin_time)) {
-      // This file will be deprecated soon. No need to implement failure
-      // handling here.
-      NOTIMPLEMENTED();
-    }
-
-    // Set the end time of this first search to null (which will
-    // show results from the future, should the user's clock have
-    // been set incorrectly).
-    options->end_time = base::Time();
-  } else {
-    // Go back |offset| months in the past. The end time is not inclusive, so
-    // use the first day of the |offset| - 1 and |offset| months (e.g. for
-    // the last month, |offset| = 1, use the first days of the last month and
-    // the current month.
-    exploded.month -= offset - 1;
-    // Set the correct year.
-    NormalizeMonths(&exploded);
-    if (!base::Time::FromLocalExploded(exploded, &options->end_time)) {
-      // This file will be deprecated soon. No need to implement failure
-      // handling here.
-      NOTIMPLEMENTED();
-    }
-
-    exploded.month -= 1;
-    // Set the correct year
-    NormalizeMonths(&exploded);
-    if (!base::Time::FromLocalExploded(exploded, &options->begin_time)) {
-      // This file will be deprecated soon. No need to implement failure
-      // handling here.
-      NOTIMPLEMENTED();
-    }
-  }
-}
-
-// Helper function for Observe that determines if there are any differences
-// between the URLs noticed for deletion and the ones we are expecting.
-static bool DeletionsDiffer(const history::URLRows& deleted_rows,
-                            const std::set<GURL>& urls_to_be_deleted) {
-  if (deleted_rows.size() != urls_to_be_deleted.size())
-    return true;
-  for (const auto& i : deleted_rows) {
-    if (urls_to_be_deleted.find(i.url()) == urls_to_be_deleted.end())
-      return true;
-  }
-  return false;
-}
-
-void BrowsingHistoryHandler::OnURLsDeleted(
-    history::HistoryService* history_service,
-    bool all_history,
-    bool expired,
-    const history::URLRows& deleted_rows,
-    const std::set<GURL>& favicon_urls) {
-  if (all_history || DeletionsDiffer(deleted_rows, urls_to_be_deleted_))
-    web_ui()->CallJavascriptFunction("historyDeleted");
-}