Refactor ShellDesktopController and ShellNativeAppWindow to allow for non-aura implementations.

extensions/browser/extensions_test.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_EXTENSIONS_TEST_H_
 #define EXTENSIONS_BROWSER_EXTENSIONS_TEST_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 29 matching lines @@
   // test-specific methods on it.
   TestExtensionsBrowserClient* extensions_browser_client() {
     return extensions_browser_client_.get();
   }
 
   // testing::Test overrides:
   void SetUp() override;
   void TearDown() override;
 
  private:
+  // TODO(yoz): Add a NotificationService here; it's used widely enough.
   scoped_ptr<content::ContentClient> content_client_;
   scoped_ptr<content::ContentBrowserClient> content_browser_client_;
   scoped_ptr<content::BrowserContext> browser_context_;
   scoped_ptr<TestExtensionsBrowserClient> extensions_browser_client_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionsTest);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_EXTENSIONS_TEST_H_