Move the "platform" wrappers in skia/ext to the skia namespace.

skia/ext/platform_canvas_mac.cc

 // Copyright (c) 2006-2008 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.
 
 #include "skia/ext/platform_canvas_mac.h"
 
 #include "base/logging.h"
 #include "skia/ext/bitmap_platform_device_mac.h"
 
-namespace gfx {
+namespace skia {
 
 PlatformCanvasMac::PlatformCanvasMac() : SkCanvas() {
 }
 
 PlatformCanvasMac::PlatformCanvasMac(int width, int height, bool is_opaque)
     : SkCanvas() {
   initialize(width, height, is_opaque);
 }
 
 PlatformCanvasMac::PlatformCanvasMac(int width,
@@ skipping 48 matching lines @@
   SkDevice* device = BitmapPlatformDeviceMac::Create(context, width, height,
                                                   is_opaque);
   return device;
 }
 
 SkDevice* PlatformCanvasMac::setBitmapDevice(const SkBitmap&) {
   NOTREACHED();
   return NULL;
 }
 
-}  // namespace gfx
+}  // namespace skia