ExtensionSystem cleanup part 2

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 <string>
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 
-class BrowserContextKeyedServiceFactory;
 class CommandLine;
 class PrefService;
 
 namespace content {
 class BrowserContext;
 class JavaScriptDialogManager;
 class WebContents;
 }
 
 namespace extensions {
 
 class ApiActivityMonitor;
 class AppSorting;
 class Extension;
 class ExtensionHost;
 class ExtensionSystem;
+class ExtensionSystemProvider;
 
 // 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 72 matching lines @@
 
   // Returns the embedder's JavaScriptDialogManager or NULL if the embedder
   // does not support JavaScript dialogs.
   virtual content::JavaScriptDialogManager* GetJavaScriptDialogManager() = 0;
 
   // Returns the embedder's ApiActivityMonitor for |context|. Returns NULL if
   // the embedder does not monitor extension API activity.
   virtual ApiActivityMonitor* GetApiActivityMonitor(
       content::BrowserContext* context) = 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 factory that provides an ExtensionSystem to be returned from
+  // ExtensionSystem::Get.
+  virtual ExtensionSystemProvider* GetExtensionSystemFactory() = 0;

[James Cook, 2014/02/12 17:18:12]

Nice, I like this approach.

 
   // 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_