Move skia_utils_gtk.cc/.h to app/gfx/ directory.

app/gfx/skia_utils_gtk.h

-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 SKIA_EXT_SKIA_UTILS_GTK_H_
-#define SKIA_EXT_SKIA_UTILS_GTK_H_
+#ifndef APP_GFX_SKIA_UTILS_GTK_H_
+#define APP_GFX_SKIA_UTILS_GTK_H_
 
 #include "third_party/skia/include/core/SkColor.h"
 
 typedef struct _GdkColor GdkColor;
 
-namespace skia {
+namespace gfx {
 
 // Converts GdkColors to the ARGB layout Skia expects.
 SkColor GdkColorToSkColor(GdkColor color);
 
 // Converts ARGB to GdkColor.
 GdkColor SkColorToGdkColor(SkColor color);
 
-}  // namespace skia
+}  // namespace gfx
 
-#endif  // SKIA_EXT_SKIA_UTILS_GTK_H_
+#endif  // APP_GFX_SKIA_UTILS_GTK_H_