Eliminate NOTIFICATION_HISTORY_LOADED notification

chrome/browser/safe_browsing/incident_reporting/last_download_finder.cc

Index: chrome/browser/safe_browsing/incident_reporting/last_download_finder.cc
diff --git a/chrome/browser/safe_browsing/incident_reporting/last_download_finder.cc b/chrome/browser/safe_browsing/incident_reporting/last_download_finder.cc
index b829960180fad95137d5d39a9559e24f17d4a9b3..69a5bce853b4b00b398c3df7d61dbfe19c934f9c 100644
--- a/chrome/browser/safe_browsing/incident_reporting/last_download_finder.cc
+++ b/chrome/browser/safe_browsing/incident_reporting/last_download_finder.cc
@@ -112,21 +112,21 @@ scoped_ptr<LastDownloadFinder> LastDownloadFinder::Create(
   return finder.Pass();
 }
 
-LastDownloadFinder::LastDownloadFinder() : weak_ptr_factory_(this) {
+LastDownloadFinder::LastDownloadFinder()
+    : weak_ptr_factory_(this), history_service_observer_(this) {
 }
 
 LastDownloadFinder::LastDownloadFinder(const std::vector<Profile*>& profiles,
                                        const LastDownloadCallback& callback)
-    : callback_(callback), weak_ptr_factory_(this) {
+    : callback_(callback),
+      weak_ptr_factory_(this),
+      history_service_observer_(this) {
   // Observe profile lifecycle events so that the finder can begin or abandon
   // the search in profiles while it is running.
   notification_registrar_.Add(this,
                               chrome::NOTIFICATION_PROFILE_ADDED,
                               content::NotificationService::AllSources());
   notification_registrar_.Add(this,
-                              chrome::NOTIFICATION_HISTORY_LOADED,
-                              content::NotificationService::AllSources());
-  notification_registrar_.Add(this,
                               chrome::NOTIFICATION_PROFILE_DESTROYED,
                               content::NotificationService::AllSources());
 
@@ -147,7 +147,7 @@ void LastDownloadFinder::SearchInProfile(Profile* profile) {
 
   // Exit early if already processing this profile. This could happen if, for
   // example, NOTIFICATION_PROFILE_ADDED arrives after construction while
-  // waiting for NOTIFICATION_HISTORY_LOADED.
+  // waiting for OnHistoryServiceLoaded.
   if (std::find(profiles_.begin(), profiles_.end(), profile) !=
       profiles_.end()) {
     return;
@@ -165,7 +165,10 @@ void LastDownloadFinder::SearchInProfile(Profile* profile) {
         base::Bind(&LastDownloadFinder::OnDownloadQuery,
                    weak_ptr_factory_.GetWeakPtr(),
                    profile));
-  }  // else wait until history is loaded.
+  } else {
+    // else wait until history is loaded.
+    history_service_observer_.Add(history_service);
+  }
 }
 
 void LastDownloadFinder::OnProfileHistoryLoaded(
@@ -242,16 +245,24 @@ void LastDownloadFinder::Observe(int type,
     case chrome::NOTIFICATION_PROFILE_ADDED:
       SearchInProfile(content::Source<Profile>(source).ptr());
       break;
-    case chrome::NOTIFICATION_HISTORY_LOADED:
-      OnProfileHistoryLoaded(content::Source<Profile>(source).ptr(),
-                             content::Details<HistoryService>(details).ptr());
-      break;
-    case chrome::NOTIFICATION_PROFILE_DESTROYED:
+    case chrome::NOTIFICATION_PROFILE_DESTROYED: {
       AbandonSearchInProfile(content::Source<Profile>(source).ptr());
+      HistoryService* history_service =
+          HistoryServiceFactory::GetForProfileIfExists(
+              content::Source<Profile>(source).ptr(), Profile::IMPLICIT_ACCESS);
+      if (history_service)
+        history_service_observer_.Remove(history_service);
       break;
+    }
     default:
       break;
   }
 }
 
+void LastDownloadFinder::OnHistoryServiceLoaded(
+    HistoryService* history_service) {
+  OnProfileHistoryLoaded(history_service->profile(), history_service);
+  history_service_observer_.Remove(history_service);
+}
+
 }  // namespace safe_browsing