No longer start BG mode until a BackgroundContents is loaded

chrome/browser/background/background_contents_service.cc

Index: chrome/browser/background/background_contents_service.cc
diff --git a/chrome/browser/background/background_contents_service.cc b/chrome/browser/background/background_contents_service.cc
index 150f8a94b01f44d0e8f8b7d2ff97a6d56ef280aa..11bd78c703f7766cd460e8f2d12c5887d7cdff7a 100644
--- a/chrome/browser/background/background_contents_service.cc
+++ b/chrome/browser/background/background_contents_service.cc
@@ -216,19 +216,24 @@ void BackgroundContentsService::Observe(
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
   switch (type) {
-    case chrome::NOTIFICATION_EXTENSIONS_READY:
-      LoadBackgroundContentsFromManifests(
-          content::Source<Profile>(source).ptr());
-      LoadBackgroundContentsFromPrefs(content::Source<Profile>(source).ptr());
+    case chrome::NOTIFICATION_EXTENSIONS_READY: {
+      Profile* profile = content::Source<Profile>(source).ptr();
+      LoadBackgroundContentsFromManifests(profile);
+      LoadBackgroundContentsFromPrefs(profile);
+      SendChangeNotification(profile);
       break;
+    }
     case chrome::NOTIFICATION_BACKGROUND_CONTENTS_DELETED:
       BackgroundContentsShutdown(
           content::Details<BackgroundContents>(details).ptr());
+      SendChangeNotification(content::Source<Profile>(source).ptr());
       break;
     case chrome::NOTIFICATION_BACKGROUND_CONTENTS_CLOSED:
       DCHECK(IsTracked(content::Details<BackgroundContents>(details).ptr()));
       UnregisterBackgroundContents(
           content::Details<BackgroundContents>(details).ptr());
+      // CLOSED is always followed by a DELETED notification so we'll send our
+      // change notification there.
       break;
     case chrome::NOTIFICATION_BACKGROUND_CONTENTS_NAVIGATED: {
       DCHECK(IsTracked(content::Details<BackgroundContents>(details).ptr()));
@@ -248,6 +253,7 @@ void BackgroundContentsService::Observe(
           break;
       }
       RegisterBackgroundContents(bgcontents);
+      SendChangeNotification(profile);

[Mihai Parparita -not on Chrome, 2012/05/03 00:54:11]

Why would a navigation cause the list of background contents to change?

[Andrew T Wilson (Slow), 2012/05/03 07:42:56]

It doesn't change the list of background content *objects*, but it *does* change
the list of registered background content URLs (we don't register them until
they have navigated, because that's the first time we actually get the URL).

But, we probably don't need to send a change notification in this case (I added
this originally when IsBackgroundApp() was going to only look at registered
URLs), so I'll remove this.

       break;
     }
     case chrome::NOTIFICATION_EXTENSION_LOADED: {
@@ -272,6 +278,7 @@ void BackgroundContentsService::Observe(
 
       // Remove any "This extension has crashed" balloons.
       ScheduleCloseBalloon(extension->id());
+      SendChangeNotification(profile);
       break;
     }
     case chrome::NOTIFICATION_EXTENSION_PROCESS_TERMINATED:
@@ -311,12 +318,15 @@ void BackgroundContentsService::Observe(
           ShutdownAssociatedBackgroundContents(
               ASCIIToUTF16(content::Details<UnloadedExtensionInfo>(details)->
                   extension->id()));
+          SendChangeNotification(content::Source<Profile>(source).ptr());
           break;
         case extension_misc::UNLOAD_REASON_UPDATE: {
           // If there is a manifest specified background page, then shut it down
           // here, since if the updated extension still has the background page,
           // then it will be loaded from LOADED callback. Otherwise, leave
           // BackgroundContents in place.
+          // We don't call SendChangeNotification here - it will be generated
+          // from the LOADED callback.
           const Extension* extension =
               content::Details<UnloadedExtensionInfo>(details)->extension;
           if (extension->has_background_page())
@@ -376,6 +386,13 @@ void BackgroundContentsService::LoadBackgroundContentsFromPrefs(
   }
 }
 
+void BackgroundContentsService::SendChangeNotification(Profile* profile) {
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_BACKGROUND_CONTENTS_SERVICE_CHANGED,
+      content::Source<Profile>(profile),
+      content::Details<BackgroundContentsService>(this));
+}
+
 void BackgroundContentsService::LoadBackgroundContentsForExtension(
     Profile* profile,
     const std::string& extension_id) {
@@ -510,6 +527,22 @@ void BackgroundContentsService::RegisterBackgroundContents(
   pref->SetWithoutPathExpansion(UTF16ToUTF8(appid), dict);
 }
 
+bool BackgroundContentsService::HasRegisteredBackgroundContents(
+    const string16& app_id) {
+  if (!prefs_)
+    return false;
+  std::string app = UTF16ToUTF8(app_id);
+  const DictionaryValue* contents =
+      prefs_->GetDictionary(prefs::kRegisteredBackgroundContents);
+  // Walk our dictionary looking for any entries with this key.

[Mihai Parparita -not on Chrome, 2012/05/03 00:54:11]

Why not use contents->HasKey(app)?

[Andrew T Wilson (Slow), 2012/05/03 07:42:56]

Ah, good idea. I should've checked DictionaryValue for a useful API first.

+  for (DictionaryValue::key_iterator it = contents->begin_keys();
+       it != contents->end_keys(); ++it) {
+    if (*it == app)
+      return true;
+  }
+  return false;
+}
+
 void BackgroundContentsService::UnregisterBackgroundContents(
     BackgroundContents* background_contents) {
   if (!prefs_)