Cleanup namespace usage in platform/graphics/[G-S]*

Source/platform/graphics/OpaqueRectTrackingContentLayerDelegateTest.cpp

 /*
  * 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:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 17 matching lines @@
 
 #include "platform/geometry/IntRect.h"
 #include "platform/graphics/Color.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "public/platform/WebFloatRect.h"
 #include "public/platform/WebRect.h"
 #include "skia/ext/platform_canvas.h"
 
 #include <gtest/gtest.h>
 
-using blink::WebRect;
-using blink::WebFloatRect;
 using namespace blink;
 
 namespace {
 
 struct PaintCallback {
     virtual void operator()(GraphicsContext&, const IntRect&) = 0;
 };
 
 class TestLayerPainterChromium : public GraphicsContextPainter {
 public:
@@ skipping 138 matching lines @@
     TestLayerPainterChromium painter(fillPartial);
     OpaqueRectTrackingContentLayerDelegate delegate(&painter);
 
     WebFloatRect opaqueRect;
     WebRect contentRect(11, 12, 389, 388);
     delegate.paintContents(skCanvas(), contentRect, false, opaqueRect);
     EXPECT_EQ_RECT(WebFloatRect(partialRect.x(), partialRect.y(), partialRect.width(), partialRect.height()), opaqueRect);
 }
 
 } // namespace