Introduce PlatformBitmap, which is a minimal helper class that wraps an SkBitmap

content/browser/renderer_host/render_widget_host_view_aura.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 "content/browser/renderer_host/render_widget_host_view_aura.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 616 matching lines @@
 
 BackingStore* RenderWidgetHostViewAura::AllocBackingStore(
     const gfx::Size& size) {
   return new BackingStoreAura(host_, size);
 }
 
 void RenderWidgetHostViewAura::CopyFromCompositingSurface(
     const gfx::Rect& src_subrect,
     const gfx::Size& dst_size,
     const base::Callback<void(bool)>& callback,
-    skia::PlatformCanvas* output) {
+    skia::PlatformBitmap* output) {
   base::ScopedClosureRunner scoped_callback_runner(base::Bind(callback, false));
 
   std::map<uint64, scoped_refptr<ui::Texture> >::iterator it =
       image_transport_clients_.find(current_surface_);
   if (it == image_transport_clients_.end())
     return;
 
   ui::Texture* container = it->second;
   DCHECK(container);
 
   gfx::Size dst_size_in_pixel = ConvertSizeToPixel(this, dst_size);
-  if (!output->initialize(
+  if (!output->Allocate(
       dst_size_in_pixel.width(), dst_size_in_pixel.height(), true))
     return;
 
   ImageTransportFactory* factory = ImageTransportFactory::GetInstance();
   GLHelper* gl_helper = factory->GetGLHelper();
   if (!gl_helper)
     return;
 
   unsigned char* addr = static_cast<unsigned char*>(
-      output->getTopDevice()->accessBitmap(true).getPixels());
+      output->GetBitmap().getPixels());
   scoped_callback_runner.Release();
   // Wrap the callback with an internal handler so that we can inject our
   // own completion handlers (where we can call AdjustSurfaceProtection).
   base::Callback<void(bool)> wrapper_callback = base::Bind(
       &RenderWidgetHostViewAura::CopyFromCompositingSurfaceFinished,
       AsWeakPtr(),
       callback);
   pending_thumbnail_tasks_.push_back(callback);
 
   // Convert |src_subrect| from the views coordinate (upper-left origin) into
@@ skipping 1204 matching lines @@
     RenderWidgetHost* widget) {
   return new RenderWidgetHostViewAura(widget);
 }
 
 // static
 void RenderWidgetHostViewPort::GetDefaultScreenInfo(WebScreenInfo* results) {
   GetScreenInfoForWindow(results, NULL);
 }
 
 }  // namespace content