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

content/browser/renderer_host/render_widget_host_impl.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_impl.h"
 
 #include <math.h>
 #include <utility>
 
 #include "base/auto_reset.h"
@@ skipping 491 matching lines @@
   gesture_event_filter_->FlingHasBeenHalted();
   if (!view_)
     return;
   view_->SetIsLoading(is_loading);
 }
 
 void RenderWidgetHostImpl::CopyFromBackingStore(
     const gfx::Rect& src_subrect,
     const gfx::Size& accelerated_dst_size,
     const base::Callback<void(bool)>& callback,
-    skia::PlatformCanvas* output) {
+    skia::PlatformBitmap* output) {
   if (view_ && is_accelerated_compositing_active_) {
     TRACE_EVENT0("browser",
         "RenderWidgetHostImpl::CopyFromBackingStore::FromCompositingSurface");
     gfx::Rect copy_rect = src_subrect.IsEmpty() ?
         gfx::Rect(view_->GetViewBounds().size()) : src_subrect;
     view_->CopyFromCompositingSurface(copy_rect,
                                       accelerated_dst_size,
                                       callback,
                                       output);
     return;
@@ skipping 1552 matching lines @@
     return;
 
   OnRenderAutoResized(new_size);
 }
 
 void RenderWidgetHostImpl::DetachDelegate() {
   delegate_ = NULL;
 }
 
 }  // namespace content