Support error handling for Surface readbacks

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 <set>
 #include <utility>
 
@@ skipping 657 matching lines @@
   RejectMouseLockOrUnlockIfNecessary();
 
   // TODO(evanm): tracking this may no longer be necessary;
   // eliminate this function if so.
   SetView(NULL);
 }
 
 void RenderWidgetHostImpl::CopyFromBackingStore(
     const gfx::Rect& src_subrect,
     const gfx::Size& accelerated_dst_size,
-    const base::Callback<void(bool, const SkBitmap&)>& callback,
+    ReadbackRequestCallback& callback,
     const SkColorType color_type) {
   if (view_) {
     TRACE_EVENT0("browser",
         "RenderWidgetHostImpl::CopyFromBackingStore::FromCompositingSurface");
     gfx::Rect accelerated_copy_rect = src_subrect.IsEmpty() ?
         gfx::Rect(view_->GetViewBounds().size()) : src_subrect;
     view_->CopyFromCompositingSurface(
         accelerated_copy_rect, accelerated_dst_size, callback, color_type);
     return;
   }
 
-  callback.Run(false, SkBitmap());
+  callback.Run(SkBitmap(), content::READBACK_FAILED);
 }
 
 bool RenderWidgetHostImpl::CanCopyFromBackingStore() {
   if (view_)
     return view_->IsSurfaceAvailableForCopy();
   return false;
 }
 
 #if defined(OS_ANDROID)
 void RenderWidgetHostImpl::LockBackingStore() {
@@ skipping 1720 matching lines @@
 }
 #endif
 
 SkColorType RenderWidgetHostImpl::PreferredReadbackFormat() {
   if (view_)
     return view_->PreferredReadbackFormat();
   return kN32_SkColorType;
 }
 
 }  // namespace content