Move c/r/extensions/* into extensions namespace

chrome/renderer/extensions/chrome_v8_context_set.h

 // Copyright (c) 2011 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_CONTEXT_SET_H_
 #define CHROME_RENDERER_EXTENSIONS_CHROME_V8_CONTEXT_SET_H_
 
 #include <set>
 #include <string>
 
 #include "base/basictypes.h"
 #include "v8/include/v8.h"
 
-class ChromeV8Context;
 class GURL;
 
 namespace base {
 class ListValue;
 }
 
 namespace content {
 class RenderView;
 }
 
 namespace v8 {
 class Context;
 }
 
+namespace extensions {
+class ChromeV8Context;
+
 // A container of ExtensionBindingsContext. Since calling JavaScript within a
 // context can cause any number of contexts to be created or destroyed, this
 // has additional smarts to help with the set changing underneath callers.
 class ChromeV8ContextSet {
  public:
   ChromeV8ContextSet();
   ~ChromeV8ContextSet();
 
   int size() const;
 
@@ skipping 27 matching lines @@
                                   const base::ListValue& arguments,
                                   content::RenderView* render_view,
                                   const GURL& event_url) const;
 
  private:
   ContextSet contexts_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeV8ContextSet);
 };
 
+}  // namespace extensions
+
 #endif  // CHROME_RENDERER_EXTENSIONS_CHROME_V8_CONTEXT_SET_H_