Makes GetComponentExtensionResourceManager() thread-safe.

extensions/browser/test_extensions_browser_client.h

 // Copyright 2014 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_TEST_EXTENSIONS_BROWSER_CLIENT_H_
 #define EXTENSIONS_BROWSER_TEST_EXTENSIONS_BROWSER_CLIENT_H_
 
 #include "base/compiler_specific.h"
 #include "extensions/browser/extensions_browser_client.h"
 #include "extensions/browser/updater/extension_cache.h"
@@ skipping 62 matching lines @@
   void PermitExternalProtocolHandler() override;
   scoped_ptr<AppSorting> CreateAppSorting() override;
   bool IsRunningInForcedAppMode() override;
   ApiActivityMonitor* GetApiActivityMonitor(
       content::BrowserContext* context) override;
   ExtensionSystemProvider* GetExtensionSystemFactory() override;
   void RegisterExtensionFunctions(
       ExtensionFunctionRegistry* registry) const override;
   scoped_ptr<RuntimeAPIDelegate> CreateRuntimeAPIDelegate(
       content::BrowserContext* context) const override;
-  ComponentExtensionResourceManager* GetComponentExtensionResourceManager()
-      override;
+  const ComponentExtensionResourceManager*
+  GetComponentExtensionResourceManager() override;
   void BroadcastEventToRenderers(const std::string& event_name,
                                  scoped_ptr<base::ListValue> args) override;
   net::NetLog* GetNetLog() override;
   ExtensionCache* GetExtensionCache() override;
   bool IsBackgroundUpdateAllowed() override;
   bool IsMinBrowserVersionSupported(const std::string& min_version) override;
 
  private:
   content::BrowserContext* main_context_;       // Not owned.
   content::BrowserContext* incognito_context_;  // Not owned, defaults to NULL.
 
   // Not owned, defaults to NULL.
   ProcessManagerDelegate* process_manager_delegate_;
 
   // Not owned, defaults to NULL.
   ExtensionSystemProvider* extension_system_factory_;
 
   scoped_ptr<ExtensionCache> extension_cache_;
 
   DISALLOW_COPY_AND_ASSIGN(TestExtensionsBrowserClient);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_TEST_EXTENSIONS_BROWSER_CLIENT_H_