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

Source/platform/image-decoders/jpeg/JPEGImageDecoderTest.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 26 matching lines @@
 #include "public/platform/WebData.h"
 #include "public/platform/WebSize.h"
 #include "public/platform/WebUnitTestSupport.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/StringHasher.h"
 
 #include <gtest/gtest.h>
 
 using namespace blink;
-using namespace blink;
 
 static const size_t LargeEnoughSize = 1000 * 1000;
 
 namespace {
 
 PassRefPtr<SharedBuffer> readFile(const char* fileName)
 {
     String filePath = Platform::current()->unitTestSupport()->webKitRootDir();
     filePath.append(fileName);
 
@@ skipping 159 matching lines @@
 TEST(JPEGImageDecoderTest, yuv)
 {
     const char* jpegFile = "/LayoutTests/fast/images/resources/lenna.jpg"; // 256x256, YUV 4:2:0
     unsigned outputYWidth, outputYHeight, outputUVWidth, outputUVHeight;
     readYUV(LargeEnoughSize, &outputYWidth, &outputYHeight, &outputUVWidth, &outputUVHeight, jpegFile);
     EXPECT_EQ(256u, outputYWidth);
     EXPECT_EQ(256u, outputYHeight);
     EXPECT_EQ(128u, outputUVWidth);
     EXPECT_EQ(128u, outputUVHeight);
 }