Eliminate NOTIFICATION_HISTORY_LOADED notification

chrome/browser/history/in_memory_url_index.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/history/in_memory_url_index.h"
 
 #include "base/debug/trace_event.h"
 #include "base/files/file_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/bookmarks/bookmark_model_factory.h"
@@ skipping 85 matching lines @@
     : profile_(profile),
       history_service_(history_service),
       history_client_(history_client),
       history_dir_(history_dir),
       languages_(languages),
       private_data_(new URLIndexPrivateData),
       restore_cache_observer_(NULL),
       save_cache_observer_(NULL),
       shutdown_(false),
       restored_(false),
-      needs_to_be_cached_(false) {
+      needs_to_be_cached_(false),
+      history_service_observer_(this) {
   InitializeSchemeWhitelist(&scheme_whitelist_);
   if (profile) {
     // TODO(mrossetti): Register for language change notifications.
     content::Source<Profile> source(profile);
     registrar_.Add(this, chrome::NOTIFICATION_HISTORY_URLS_MODIFIED,
                    source);
     registrar_.Add(this, chrome::NOTIFICATION_HISTORY_URLS_DELETED, source);
   }
   if (history_service_)
-    history_service_->AddObserver(this);
+    history_service_observer_.Add(history_service_);
 }
 
 // Called only by unit tests.
 InMemoryURLIndex::InMemoryURLIndex()
     : profile_(NULL),
       history_service_(nullptr),
       history_client_(NULL),
       private_data_(new URLIndexPrivateData),
       restore_cache_observer_(NULL),
       save_cache_observer_(NULL),
       shutdown_(false),
       restored_(false),
-      needs_to_be_cached_(false) {
+      needs_to_be_cached_(false),
+      history_service_observer_(this) {
   InitializeSchemeWhitelist(&scheme_whitelist_);
 }
 
 InMemoryURLIndex::~InMemoryURLIndex() {
   // If there was a history directory (which there won't be for some unit tests)
   // then insure that the cache has already been saved.
   DCHECK(history_dir_.empty() || !needs_to_be_cached_);
 }
 
 void InMemoryURLIndex::Init() {
   PostRestoreFromCacheFileTask();
 }
 
 void InMemoryURLIndex::ShutDown() {
-  if (history_service_)
-    history_service_->RemoveObserver(this);
+  history_service_observer_.RemoveAll();
   registrar_.RemoveAll();
   cache_reader_tracker_.TryCancelAll();
   shutdown_ = true;
   base::FilePath path;
   if (!GetCacheFilePath(&path))
     return;
   private_data_tracker_.TryCancelAll();
   URLIndexPrivateData::WritePrivateDataToCacheFileTask(private_data_, path);
   needs_to_be_cached_ = false;
 }
@@ skipping 34 matching lines @@
                                const content::NotificationDetails& details) {
   switch (notification_type) {
     case chrome::NOTIFICATION_HISTORY_URLS_MODIFIED:
       OnURLsModified(
           content::Details<history::URLsModifiedDetails>(details).ptr());
       break;
     case chrome::NOTIFICATION_HISTORY_URLS_DELETED:
       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.
       break;
   }
 }
 
 void InMemoryURLIndex::OnURLVisited(HistoryService* history_service,
                                     ui::PageTransition transition,
                                     const URLRow& row,
@@ skipping 82 matching lines @@
     // When unable to restore from the cache file delete the cache file, if
     // it exists, and then rebuild from the history database if it's available,
     // otherwise wait until the history database loaded and then rebuild.
     base::FilePath path;
     if (!GetCacheFilePath(&path) || shutdown_)
       return;
     content::BrowserThread::PostBlockingPoolTask(
         FROM_HERE, base::Bind(DeleteCacheFile, path));
     HistoryService* service =
         HistoryServiceFactory::GetForProfileWithoutCreating(profile_);
-    if (service && service->backend_loaded()) {
-      ScheduleRebuildFromHistory();
-    } else {
-      registrar_.Add(this, chrome::NOTIFICATION_HISTORY_LOADED,
-                     content::Source<Profile>(profile_));
+    if (service) {
+      if (!service->backend_loaded()) {
+        history_service_observer_.Add(service);

[sdefresne, 2014/11/05 14:51:52]

InMemoryURLIndex constructor already register 'this' as an observer, so this
line should either be removed or protected with
"!history_service_observer_.IsObserving(service))" if this is required to make
the tests pass.

[nshaik, 2014/11/06 02:05:12]

Done.

+      } else {
+        ScheduleRebuildFromHistory();
+      }
     }
   }
 }
 
 // Restoring from the History DB -----------------------------------------------
 
 void InMemoryURLIndex::ScheduleRebuildFromHistory() {
   HistoryService* service =
       HistoryServiceFactory::GetForProfile(profile_,
                                            Profile::EXPLICIT_ACCESS);
@@ skipping 53 matching lines @@
         FROM_HERE,
         base::Bind(DeleteCacheFile, path));
   }
 }
 
 void InMemoryURLIndex::OnCacheSaveDone(bool succeeded) {
   if (save_cache_observer_)
     save_cache_observer_->OnCacheSaveFinished(succeeded);
 }
 
+void InMemoryURLIndex::OnHistoryServiceLoaded(HistoryService* history_service) {
+  ScheduleRebuildFromHistory();
+  history_service_observer_.Remove(history_service);

[sdefresne, 2014/11/05 14:51:52]

Remove this line, otherwise InMemoryURLIndex::OnURLVisited won't be called.

[nshaik, 2014/11/06 02:05:12]

My bad. fixed it.

+}
+
 }  // namespace history