Removing duplicate 'using namespace blink;' in platform and web

Source/web/tests/CustomEventTest.cpp

 /*
  * Copyright (C) 2013 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 31 matching lines @@
 #include "public/web/WebFrame.h"
 #include "public/web/WebView.h"
 #include "v8.h"
 #include "web/WebLocalFrameImpl.h"
 #include "web/WebViewImpl.h"
 #include "web/tests/FrameTestHelpers.h"
 
 #include <gtest/gtest.h>
 
 using namespace blink;
-using namespace blink;
 
 namespace {
 
 class TestListener : public V8AbstractEventListener {
 public:
     virtual bool operator==(const EventListener&)
     {
         return true;
     }
 
@@ skipping 46 matching lines @@
     V8TestingScope scope(isolate);
     customEvent.initCustomEvent("blah", false, false, WebSerializedScriptValue::serialize(v8::Boolean::New(isolate, true)));
     RefPtr<EventListener> listener = TestListener::create(scope.scriptState());
     frame->frame()->document()->addEventListener("blah", listener, false);
     frame->frame()->document()->dispatchEvent(event);
 
     Platform::current()->unitTestSupport()->unregisterAllMockedURLs();
 }
 
 }