Cleanup namespace usage in Source/web/*.h

Source/web/PrerendererClientImpl.h

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 19 matching lines @@
  */
 
 #ifndef PrerendererClientImpl_h
 #define PrerendererClientImpl_h
 
 #include "core/loader/PrerendererClient.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/PassRefPtr.h"
 
 namespace blink {
+
 class Prerender;
-}
-
-namespace blink {
-
 class WebPrerendererClient;
 
-class PrerendererClientImpl FINAL : public NoBaseWillBeGarbageCollected<PrerendererClientImpl>, public blink::PrerendererClient {
+class PrerendererClientImpl FINAL : public NoBaseWillBeGarbageCollected<PrerendererClientImpl>, public PrerendererClient {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(PrerendererClientImpl);
     WTF_MAKE_NONCOPYABLE(PrerendererClientImpl);
 public:
     explicit PrerendererClientImpl(WebPrerendererClient*);
 
-    void willAddPrerender(blink::Prerender*) OVERRIDE;
+    void willAddPrerender(Prerender*) OVERRIDE;
 
-    virtual void trace(blink::Visitor* visitor) OVERRIDE { blink::PrerendererClient::trace(visitor); }
+    virtual void trace(Visitor* visitor) OVERRIDE { PrerendererClient::trace(visitor); }
 
 private:
     WebPrerendererClient* m_client;
 };
 
 }
 
 #endif // PrerendererClientImpl_h