Merge search engines sync data type with Preferences. Sync the default search provider. Add some defensive measures to prevent deletion of the default search engine or unnecessarily uniquifying keywords.

TEST=Ensure that the default search provider syncs when the Preferences sync data type is enabled. Ensure that the normal search engine syncing changes (add, update, delete) all work.
BUG=15548
Review URL: http://codereview.chromium.org/8334030

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@109882 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 120 insertions, 14 deletions

diff --git a/chrome/browser/search_engines/template_url_service.cc b/chrome/browser/search_engines/template_url_service.cc
index b9ea5de..fa85ab9 100644
--- a/chrome/browser/search_engines/template_url_service.cc
+++ b/chrome/browser/search_engines/template_url_service.cc
@@ -113,7 +113,8 @@ TemplateURLService::TemplateURLService(Profile* profile)
       time_provider_(&base::Time::Now),
       models_associated_(false),
       processing_syncer_changes_(false),
-      sync_processor_(NULL) {
+      sync_processor_(NULL),
+      pending_synced_default_search_(false) {
   DCHECK(profile_);
   Init(NULL, 0);
 }
@@ -131,7 +132,8 @@ TemplateURLService::TemplateURLService(const Initializer* initializers,
       time_provider_(&base::Time::Now),
       models_associated_(false),
       processing_syncer_changes_(false),
-      sync_processor_(NULL) {
+      sync_processor_(NULL),
+      pending_synced_default_search_(false) {
   Init(initializers, count);
 }
 
@@ -457,7 +459,7 @@ const TemplateURL* TemplateURLService::FindNewDefaultSearchProvider() {
   scoped_ptr<TemplateURL> prepopulated_default(
       TemplateURLPrepopulateData::GetPrepopulatedDefaultSearch(GetPrefs()));
   for (TemplateURLVector::iterator i = template_urls_.begin();
-      i != template_urls_.end(); ) {
+       i != template_urls_.end(); ++i) {
     if ((*i)->prepopulate_id() == prepopulated_default->prepopulate_id())
       return *i;
   }
@@ -579,12 +581,17 @@ void TemplateURLService::OnWebDataServiceRequestDone(
     // Note that this saves the default search provider to prefs.
     SetDefaultSearchProviderNoNotify(default_search_provider);
   } else {
-    // If we had a managed default, replace it with the first provider of
-    // the list.
-    if (database_specified_a_default &&
-        NULL == default_search_provider &&
-        !template_urls.empty())
+    // If we had a managed default, replace it with the synced default if
+    // applicable, or the first provider of the list.
+    const TemplateURL* synced_default = GetPendingSyncedDefaultSearchProvider();
+    if (synced_default) {
+      default_search_provider = synced_default;
+      pending_synced_default_search_ = false;
+    } else if (database_specified_a_default &&
+               NULL == default_search_provider &&
+               !template_urls.empty()) {
       default_search_provider = template_urls[0];
+    }
 
     // If the default search provider existed previously, then just
     // set the member variable. Otherwise, we'll set it using the method
@@ -651,6 +658,27 @@ void TemplateURLService::Observe(int type,
   } else if (type == chrome::NOTIFICATION_PREF_CHANGED) {
     const std::string* pref_name = content::Details<std::string>(details).ptr();
     if (!pref_name || default_search_prefs_->IsObserved(*pref_name)) {
+      // Listen for changes to the default search from Sync. If it is
+      // specifically the synced default search provider GUID that changed, we
+      // have to set it (or wait for it).
+      PrefService* prefs = GetPrefs();
+      if (pref_name && *pref_name == prefs::kSyncedDefaultSearchProviderGUID &&
+          prefs) {
+        const TemplateURL* new_default_search = GetTemplateURLForGUID(
+            prefs->GetString(prefs::kSyncedDefaultSearchProviderGUID));
+        if (new_default_search && !is_default_search_managed_) {
+          if (new_default_search != GetDefaultSearchProvider()) {
+            SetDefaultSearchProvider(new_default_search);
+            pending_synced_default_search_ = false;
+          }
+        } else {
+          // If it's not there, or if default search is currently managed, set a
+          // flag to indicate that we waiting on the search engine entry to come
+          // in through Sync.
+          pending_synced_default_search_ = true;
+        }
+      }
+
       // A preference related to default search engine has changed.
       // Update the model if needed.
       UpdateDefaultSearch();
@@ -708,17 +736,35 @@ SyncError TemplateURLService::ProcessSyncChanges(
         GetTemplateURLForKeyword(turl->keyword());
 
     if (iter->change_type() == SyncChange::ACTION_DELETE && existing_turl) {
-      Remove(existing_turl);
+      bool delete_default = (existing_turl == GetDefaultSearchProvider());
+
+      if (delete_default && is_default_search_managed_) {
+        NOTREACHED() << "Tried to delete managed default search provider";
+      } else {
+        if (delete_default)
+          default_search_provider_ = NULL;
+
+        Remove(existing_turl);
+
+        if (delete_default)
+          SetDefaultSearchProvider(FindNewDefaultSearchProvider());
+      }
     } else if (iter->change_type() == SyncChange::ACTION_ADD &&
                !existing_turl) {
+      std::string guid = turl->sync_guid();
       if (existing_keyword_turl)
         ResolveSyncKeywordConflict(turl.get(), &new_changes);
       // Force the local ID to 0 so we can add it.
       turl->set_id(0);
       Add(turl.release());
+
+      // Possibly set the newly added |turl| as the default search provider.
+      SetDefaultSearchProviderIfNewlySynced(guid);
     } else if (iter->change_type() == SyncChange::ACTION_UPDATE &&
                existing_turl) {
-      if (existing_keyword_turl)
+      // Possibly resolve a keyword conflict if they have the same keywords but
+      // are not the same entry.
+      if (existing_keyword_turl && existing_keyword_turl != existing_turl)
         ResolveSyncKeywordConflict(turl.get(), &new_changes);
       ResetTemplateURL(existing_turl, turl->short_name(), turl->keyword(),
           turl->url() ? turl->url()->url() : std::string());
@@ -753,6 +799,18 @@ SyncError TemplateURLService::MergeDataAndStartSyncing(
   DCHECK(!sync_processor_);
   sync_processor_ = sync_processor;
 
+  // We just started syncing, so set our wait-for-default flag if we are
+  // expecting a default from Sync.
+  if (GetPrefs()) {
+    std::string default_guid = GetPrefs()->GetString(
+        prefs::kSyncedDefaultSearchProviderGUID);
+    const TemplateURL* current_default = GetDefaultSearchProvider();
+
+    if (!default_guid.empty() &&
+        (!current_default || current_default->sync_guid() != default_guid))
+      pending_synced_default_search_ = true;
+  }
+
   // We do a lot of calls to Add/Remove/ResetTemplateURL here, so ensure we
   // don't step on our own toes.
   AutoReset<bool> processing_changes(&processing_syncer_changes_, true);
@@ -812,6 +870,7 @@ SyncError TemplateURLService::MergeDataAndStartSyncing(
                                        &new_changes);
         local_data_map.erase(old_guid);
       } else {
+        std::string guid = sync_turl->sync_guid();
         // Keyword conflict is possible in this case. Resolve it first before
         // adding the new TemplateURL. Note that we don't remove the local TURL
         // from local_data_map in this case as it may still need to be pushed to
@@ -820,6 +879,9 @@ SyncError TemplateURLService::MergeDataAndStartSyncing(
         // Force the local ID to 0 so we can add it.
         sync_turl->set_id(0);
         Add(sync_turl.release());
+
+        // Possibly set the newly added |turl| as the default search provider.
+        SetDefaultSearchProviderIfNewlySynced(guid);
       }
     }
   }  // for
@@ -952,7 +1014,7 @@ void TemplateURLService::SetKeywordSearchTermsForURL(const TemplateURL* t_url,
 }
 
 void TemplateURLService::Init(const Initializer* initializers,
-                            int num_initializers) {
+                              int num_initializers) {
   // Register for notifications.
   if (profile_) {
     // TODO(sky): bug 1166191. The keywords should be moved into the history
@@ -1488,7 +1550,14 @@ void TemplateURLService::UpdateDefaultSearch() {
       default_search_provider_ = NULL;
       RemoveNoNotify(old_default);
     }
-    SetDefaultSearchProviderNoNotify(FindNewDefaultSearchProvider());
+
+    // The likely default should be from Sync if we were waiting on Sync.
+    // Otherwise, it should be FindNewDefaultSearchProvider.
+    const TemplateURL* synced_default = GetPendingSyncedDefaultSearchProvider();
+    if (synced_default)
+      pending_synced_default_search_ = false;
+    SetDefaultSearchProviderNoNotify(synced_default ? synced_default :
+        FindNewDefaultSearchProvider());
   }
   NotifyObservers();
 }
@@ -1520,9 +1589,17 @@ void TemplateURLService::SetDefaultSearchProviderNoNotify(
     }
   }
 
-  if (!is_default_search_managed_)
+  if (!is_default_search_managed_) {
     SaveDefaultSearchProviderToPrefs(url);
 
+    // If we are syncing, we want to set the synced pref that will notify other
+    // instances to change their default to this new search provider.
+    if (sync_processor_ && !url->sync_guid().empty() && GetPrefs()) {
+      GetPrefs()->SetString(prefs::kSyncedDefaultSearchProviderGUID,
+                            url->sync_guid());
+    }
+  }
+
   if (service_.get())
     service_->SetDefaultSearchProvider(url);
 
@@ -1681,7 +1758,8 @@ bool TemplateURLService::ResolveSyncKeywordConflict(
 
   const TemplateURL* existing_turl =
       GetTemplateURLForKeyword(sync_turl->keyword());
-  if (!existing_turl)
+  // If there is no conflict, or it's just conflicting with itself, return.
+  if (!existing_turl || existing_turl->sync_guid() == sync_turl->sync_guid())
     return false;
 
   if (existing_turl->last_modified() > sync_turl->last_modified() ||
@@ -1745,6 +1823,34 @@ void TemplateURLService::MergeSyncAndLocalURLDuplicates(
   }
 }
 
+void TemplateURLService::SetDefaultSearchProviderIfNewlySynced(
+    const std::string& guid) {
+  // If we're not syncing or if default search is managed by policy, ignore.
+  if (!sync_processor_ || is_default_search_managed_)
+    return;
+
+  PrefService* prefs = GetPrefs();
+  if (prefs && pending_synced_default_search_ &&
+      prefs->GetString(prefs::kSyncedDefaultSearchProviderGUID) == guid) {
+    // Make sure this actually exists. We should not be calling this unless we
+    // really just added this TemplateURL.
+    const TemplateURL* turl_from_sync = GetTemplateURLForGUID(guid);
+    DCHECK(turl_from_sync);
+    SetDefaultSearchProvider(turl_from_sync);
+    pending_synced_default_search_ = false;
+  }
+}
+
+const TemplateURL* TemplateURLService::GetPendingSyncedDefaultSearchProvider() {
+  PrefService* prefs = GetPrefs();
+  if (!prefs || !pending_synced_default_search_)
+    return NULL;
+
+  // Could be NULL if no such thing exists.
+  return GetTemplateURLForGUID(
+      prefs->GetString(prefs::kSyncedDefaultSearchProviderGUID));
+}
+
 void TemplateURLService::PatchMissingSyncGUIDs(
     std::vector<TemplateURL*>* template_urls) {
   DCHECK(template_urls);