Allow app_shell to run past extension manifest parsing

extensions/browser/process_manager.cc

 // Copyright 2013 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 "extensions/browser/process_manager.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
@@ skipping 576 matching lines @@
        // (or an incognito profile from this profile) is ready.
        if (DeferLoadingBackgroundHosts())
          break;
 
       CreateBackgroundHostsForProfileStartup();
       break;
     }
 
     case chrome::NOTIFICATION_EXTENSION_LOADED: {
       BrowserContext* context = content::Source<BrowserContext>(source).ptr();
-      ExtensionService* service =
-          ExtensionSystem::GetForBrowserContext(context)->extension_service();
-      if (service->is_ready()) {
+      ExtensionSystem* system = ExtensionSystem::GetForBrowserContext(context);
+      if (system->ready().is_signaled()) {
+        // The extension system is ready, so create the background host.
         const Extension* extension =
             content::Details<const Extension>(details).ptr();
         CreateBackgroundHostForExtensionLoad(this, extension);
       }
       break;
     }
 
     case chrome::NOTIFICATION_EXTENSION_UNLOADED: {
       const Extension* extension =
           content::Details<UnloadedExtensionInfo>(details)->extension;
@@ skipping 263 matching lines @@
 }
 
 bool IncognitoProcessManager::IsIncognitoEnabled(const Extension* extension) {
   // Keep in sync with duplicate in extension_info_map.cc.
   ExtensionService* service = ExtensionSystem::GetForBrowserContext(
       GetBrowserContext())->extension_service();
   return extension_util::IsIncognitoEnabled(extension->id(), service);
 }
 
 }  // namespace extensions