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

Source/platform/graphics/Path.cpp

 /*
  * Copyright (C) 2003, 2006 Apple Computer, Inc.  All rights reserved.
  *                     2006 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2013 Google Inc. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
@@ skipping 485 matching lines @@
 }
 
 #if ENABLE(ASSERT)
 bool ellipseIsRenderable(float startAngle, float endAngle)
 {
     return (std::abs(endAngle - startAngle) < twoPiFloat)
         || WebCoreFloatNearlyEqual(std::abs(endAngle - startAngle), twoPiFloat);
 }
 #endif
 
-}
+} // namespace blink