Simplify platform_canvas.h by recognizing that PlatformCanvas does not actually extend

ui/gfx/image/image_skia_operations.cc

 // 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.
 
 #include "ui/gfx/image/image_skia_operations.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "skia/ext/image_operations.h"
-#include "skia/ext/platform_canvas.h"
 #include "ui/base/layout.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/image/canvas_image_source.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/image/image_skia_rep.h"
 #include "ui/gfx/image/image_skia_source.h"
 #include "ui/gfx/insets.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/size.h"
 #include "ui/gfx/size_conversions.h"
 #include "ui/gfx/skbitmap_operations.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/gfx/switches.h"
 
 namespace gfx {
 namespace {
 
 bool ScalingEnabled() {
   static bool scale_images = !CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kDisableScalingInImageSkiaOperations);
   return scale_images;
 }
 
 // Creates 2x scaled image of the give |source|.
 ImageSkiaRep Create2XImageSkiaRep(const ImageSkiaRep& source) {
   gfx::Size size(source.GetWidth() * 2.0f, source.GetHeight() * 2.0f);
-  skia::PlatformCanvas canvas(size.width(), size.height(), false);
+
+  SkBitmap resized_bitmap;
+  resized_bitmap.setConfig(SkBitmap::kARGB_8888_Config, size.width(), 
+                           size.height());
+  if (!resized_bitmap.allocPixels())
+    SK_CRASH();
+  SkCanvas canvas(resized_bitmap);
   SkRect resized_bounds = RectToSkRect(gfx::Rect(size));
   canvas.drawBitmapRect(source.sk_bitmap(), NULL, resized_bounds);
-  SkBitmap resized_bitmap = canvas.getDevice()->accessBitmap(false);
   return ImageSkiaRep(resized_bitmap, ui::SCALE_FACTOR_200P);
 }
 
 // A utility function to synchronize the scale factor of the two images.
 // When the command line option "--disable-scaling-in-image-skia-operation"
 // is provided, this function will fail if the scale factors of the two images
 // are different. This assumes that the platform only supports
 // 1x and 2x scale factors.
 // TODO(oshima): Remove and replace this with plain CHECK once
 // 2x images for all resources are provided.
@@ skipping 402 matching lines @@
     const ImageSkia& source,
     const ShadowValues& shadows) {
   const gfx::Insets shadow_padding = -gfx::ShadowValue::GetMargin(shadows);
   gfx::Size shadow_image_size = source.size();
   shadow_image_size.Enlarge(shadow_padding.width(),
                             shadow_padding.height());
   return ImageSkia(new DropShadowSource(source, shadows), shadow_image_size);
 }
 
 }  // namespace gfx