Fix app_shell shutdown crash due to BrowserContextKeyedServices

extensions/browser/extensions_browser_client.h

 // 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.
 
 #ifndef EXTENSIONS_BROWSER_EXTENSIONS_BROWSER_CLIENT_H_
 #define EXTENSIONS_BROWSER_EXTENSIONS_BROWSER_CLIENT_H_
 
+#include <vector>
+
 #include "base/memory/scoped_ptr.h"
 
+class BrowserContextKeyedServiceFactory;
 class CommandLine;
 class PrefService;
 
 namespace content {
 class BrowserContext;
 class JavaScriptDialogManager;
 }
 
 namespace extensions {
 
 class AppSorting;
+class ExtensionSystem;
 
 // Interface to allow the extensions module to make browser-process-specific
 // queries of the embedder. Should be Set() once in the browser process.
 //
 // NOTE: Methods that do not require knowledge of browser concepts should be
 // added in ExtensionsClient (extensions/common/extensions_client.h) even if
 // they are only used in the browser process.
 class ExtensionsBrowserClient {
  public:
   virtual ~ExtensionsBrowserClient() {}
@@ skipping 49 matching lines @@
   // Creates a new AppSorting instance.
   virtual scoped_ptr<AppSorting> CreateAppSorting() = 0;
 
   // Return true if the system is run in forced app mode.
   virtual bool IsRunningInForcedAppMode() = 0;
 
   // Returns the embedder's JavaScriptDialogManager or NULL if the embedder
   // does not support JavaScript dialogs.
   virtual content::JavaScriptDialogManager* GetJavaScriptDialogManager() = 0;
 
+  // Returns the dependencies of ExtensionSystem. May return an empty list.
+  virtual std::vector<BrowserContextKeyedServiceFactory*>
+      GetExtensionSystemDependencies() = 0;
+
+  // Creates a new ExtensionSystem for |context|.
+  virtual ExtensionSystem* CreateExtensionSystem(
+      content::BrowserContext* context) = 0;
+
   // Returns the single instance of |this|.
   static ExtensionsBrowserClient* Get();
 
   // Initialize the single instance.
   static void Set(ExtensionsBrowserClient* client);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_EXTENSIONS_BROWSER_CLIENT_H_