[Sync] Make SESSIONS an implicit type

chrome/browser/sync/sync_prefs.cc

 // Copyright (c) 2012 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/sync/sync_prefs.h"
 
 #include "base/logging.h"
 #include "base/prefs/public/pref_member.h"
 #include "base/string_number_conversions.h"
 #include "base/values.h"
@@ skipping 301 matching lines @@
     case syncer::SEARCH_ENGINES:
       return prefs::kSyncSearchEngines;
     case syncer::SESSIONS:
       return prefs::kSyncSessions;
     case syncer::APP_NOTIFICATIONS:
       return prefs::kSyncAppNotifications;
     case syncer::HISTORY_DELETE_DIRECTIVES:
       return prefs::kSyncHistoryDeleteDirectives;
     case syncer::SYNCED_NOTIFICATIONS:
       return prefs::kSyncSyncedNotifications;
+    case syncer::TABS:
+      return prefs::kSyncTabs;
     default:
       break;
   }
   NOTREACHED();
   return NULL;
 }
 
 #if defined(OS_CHROMEOS)
 std::string SyncPrefs::GetSpareBootstrapToken() const {
   DCHECK(CalledOnValidThread());
@@ skipping 46 matching lines @@
 void SyncPrefs::RegisterPrefGroups() {
   pref_groups_[syncer::APPS].Put(syncer::APP_NOTIFICATIONS);
   pref_groups_[syncer::APPS].Put(syncer::APP_SETTINGS);
 
   pref_groups_[syncer::AUTOFILL].Put(syncer::AUTOFILL_PROFILE);
 
   pref_groups_[syncer::EXTENSIONS].Put(syncer::EXTENSION_SETTINGS);
 
   pref_groups_[syncer::PREFERENCES].Put(syncer::SEARCH_ENGINES);
 
-  // TODO(akalin): Revisit this once UI lands.
-  pref_groups_[syncer::SESSIONS].Put(syncer::HISTORY_DELETE_DIRECTIVES);
+  pref_groups_[syncer::TYPED_URLS].Put(syncer::HISTORY_DELETE_DIRECTIVES);
+  pref_groups_[syncer::HISTORY_DELETE_DIRECTIVES].Put(syncer::SESSIONS);
+  pref_groups_[syncer::TABS].Put(syncer::SESSIONS);
 }
 
 // static
 void SyncPrefs::RegisterDataTypePreferredPref(PrefServiceSyncable* prefs,
                                               syncer::ModelType type,
                                               bool is_preferred) {
   const char* pref_name = GetPrefNameForDataType(type);
   if (!pref_name) {
     NOTREACHED();
     return;
   }
   prefs->RegisterBooleanPref(pref_name, is_preferred,
                              PrefServiceSyncable::UNSYNCABLE_PREF);
 }
 
 bool SyncPrefs::GetDataTypePreferred(syncer::ModelType type) const {
   DCHECK(CalledOnValidThread());
   if (!pref_service_) {
     return false;
   }
   const char* pref_name = GetPrefNameForDataType(type);
   if (!pref_name) {
     NOTREACHED();
     return false;
   }
+  if (type == syncer::TABS &&
+      pref_service_->GetUserPrefValue(pref_name) == NULL &&
+      pref_service_->IsUserModifiablePreference(pref_name)) {
+    // If there is no tab sync preference yet (i.e. newly enabled type),
+    // default to the session sync preference value.
+    pref_name = GetPrefNameForDataType(syncer::SESSIONS);
+  }
 
   return pref_service_->GetBoolean(pref_name);
 }
 
 void SyncPrefs::SetDataTypePreferred(
     syncer::ModelType type, bool is_preferred) {
   DCHECK(CalledOnValidThread());
   CHECK(pref_service_);
   const char* pref_name = GetPrefNameForDataType(type);
   if (!pref_name) {
     NOTREACHED();
     return;
   }
   pref_service_->SetBoolean(pref_name, is_preferred);
 }
 
 syncer::ModelTypeSet SyncPrefs::ResolvePrefGroups(
     syncer::ModelTypeSet registered_types,
     syncer::ModelTypeSet types) const {
   DCHECK(registered_types.HasAll(types));
   syncer::ModelTypeSet types_with_groups = types;
   for (PrefGroupsMap::const_iterator i = pref_groups_.begin();
       i != pref_groups_.end(); ++i) {
     if (types.Has(i->first))
       types_with_groups.PutAll(i->second);
-    else
-      types_with_groups.RemoveAll(i->second);
   }
   types_with_groups.RetainAll(registered_types);
   return types_with_groups;
 }
 
 }  // namespace browser_sync