Eliminate NOTIFICATION_HISTORY_LOADED notification

chrome/browser/history/in_memory_url_index.cc

Index: chrome/browser/history/in_memory_url_index.cc
diff --git a/chrome/browser/history/in_memory_url_index.cc b/chrome/browser/history/in_memory_url_index.cc
index 71244d31aa872a73964387b66f3dc625abd915f7..6bb0f4c4e6b7822c2f58d443c4f422fa66372837 100644
--- a/chrome/browser/history/in_memory_url_index.cc
+++ b/chrome/browser/history/in_memory_url_index.cc
@@ -137,6 +137,10 @@ void InMemoryURLIndex::Init() {
 }
 
 void InMemoryURLIndex::ShutDown() {
+  HistoryService* service =
+      HistoryServiceFactory::GetForProfileWithoutCreating(profile_);
+  if (service)
+    service->RemoveHistoryServiceObserver(this);

[sdefresne, 2014/10/20 13:15:42]

You can use ScopedObserver<> to simplify the code.

   registrar_.RemoveAll();
   cache_reader_tracker_.TryCancelAll();
   shutdown_ = true;
@@ -194,11 +198,6 @@ void InMemoryURLIndex::Observe(int notification_type,
       OnURLsDeleted(
           content::Details<history::URLsDeletedDetails>(details).ptr());
       break;
-    case chrome::NOTIFICATION_HISTORY_LOADED:
-      registrar_.Remove(this, chrome::NOTIFICATION_HISTORY_LOADED,
-                        content::Source<Profile>(profile_));
-      ScheduleRebuildFromHistory();
-      break;
     default:
       // For simplicity, the unit tests send us all notifications, even when
       // we haven't registered for them, so don't assert here.
@@ -302,8 +301,7 @@ void InMemoryURLIndex::OnCacheLoadDone(
     if (service && service->backend_loaded()) {

[sdefresne, 2014/10/20 13:15:41]

|service| can only be NULL if running tests, so rewrite as

if (service) {
  if (!service->backend_loaded()) {
    service->AddObserver(this);
  } else {
    ScheduleRebuildFromHistory();
  }
}

[nshaik, 2014/10/29 08:43:39]

Done.

       ScheduleRebuildFromHistory();
     } else {
-      registrar_.Add(this, chrome::NOTIFICATION_HISTORY_LOADED,
-                     content::Source<Profile>(profile_));
+      service->AddHistoryServiceObserver(this);
     }
   }
 }
@@ -377,4 +375,9 @@ void InMemoryURLIndex::OnCacheSaveDone(bool succeeded) {
     save_cache_observer_->OnCacheSaveFinished(succeeded);
 }
 
+void InMemoryURLIndex::HistoryServiceLoaded(HistoryService* history_service) {
+  ScheduleRebuildFromHistory();
+  history_service->RemoveHistoryServiceObserver(this);
+}
+
 }  // namespace history