Move Extension into extensions namespace

chrome/renderer/extensions/chrome_v8_extension.h

 // Copyright (c) 2012 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 CHROME_RENDERER_EXTENSIONS_CHROME_V8_EXTENSION_H_
 #define CHROME_RENDERER_EXTENSIONS_CHROME_V8_EXTENSION_H_
 #pragma once
 
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
 #include "base/string_piece.h"
 #include "chrome/renderer/extensions/chrome_v8_extension_handler.h"
 #include "chrome/renderer/native_handler.h"
 #include "v8/include/v8.h"
 
 #include <map>
 #include <set>
 #include <string>
 
 class ChromeV8Context;
-class Extension;
 class ExtensionDispatcher;
 
 namespace content {
 class RenderView;
 }
 
+namespace extensions {
+class Extension;
+}
+
 // This is a base class for chrome extension bindings.  Common features that
 // are shared by different modules go here.
 // TODO(koz): Rename this to ExtensionNativeModule.
 class ChromeV8Extension : public NativeHandler {
  public:
   typedef std::set<ChromeV8Extension*> InstanceSet;
   static const InstanceSet& GetAll();
 
   explicit ChromeV8Extension(ExtensionDispatcher* extension_dispatcher);
   virtual ~ChromeV8Extension();
 
   ExtensionDispatcher* extension_dispatcher() { return extension_dispatcher_; }
 
  protected:
   template<class T>
   static T* GetFromArguments(const v8::Arguments& args) {
     CHECK(!args.Data().IsEmpty());
     T* result = static_cast<T*>(args.Data().As<v8::External>()->Value());
     return result;
   }
 
   // Gets the render view for the current v8 context.
   static content::RenderView* GetCurrentRenderView();
 
   // Note: do not call this function before or during the chromeHidden.onLoad
   // event dispatch. The URL might not have been committed yet and might not
   // be an extension URL.
-  const ::Extension* GetExtensionForCurrentRenderView() const;
+  const extensions::Extension* GetExtensionForCurrentRenderView() const;
 
   // Returns the chromeHidden object for the current context.
   static v8::Handle<v8::Value> GetChromeHidden(const v8::Arguments& args);
 
   ExtensionDispatcher* extension_dispatcher_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ChromeV8Extension);
 };
 
 #endif  // CHROME_RENDERER_EXTENSIONS_CHROME_V8_EXTENSION_H_