cc: Unify namespaces for all test files

cc/test/pixel_test_utils.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#ifndef CC_TEST_PIXEL_TEST_UTILS_H_
+#define CC_TEST_PIXEL_TEST_UTILS_H_
+
 #include "base/file_path.h"
 
 class SkBitmap;
 
 namespace cc {
-namespace test {
 
 // Encodes a bitmap into a PNG and write to disk. Returns true on success. The
 // parent directory does not have to exist.
 bool WritePNGFile(const SkBitmap& bitmap, const FilePath& file_path);
 
 // Reads and decodes a PNG image to a bitmap. Returns true on success. The PNG
 // should have been encoded using |gfx::PNGCodec::Encode|.
 bool ReadPNGFile(const FilePath& file_path, SkBitmap* bitmap);
 
 // Compares with a PNG file on disk, and returns true if it is the same as
 // the given image. |ref_img_path| is absolute.
 bool IsSameAsPNGFile(const SkBitmap& gen_bmp, FilePath ref_img_path);
 
-}  // namespace test
 }  // namespace cc
+
+#endif  // CC_TEST_PIXEL_TEST_UTILS_H_