Support browser side thumbnailing for GPU composited pages on Windows.

content/browser/renderer_host/render_widget_host.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.h"
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 466 matching lines @@
 
 bool RenderWidgetHostImpl::CopyFromBackingStore(skia::PlatformCanvas* output) {
   BackingStore* backing_store = GetBackingStore(false);
   if (!backing_store)
     return false;
 
   return backing_store->CopyFromBackingStore(
       gfx::Rect(backing_store->size()), output);
 }
 
+#if !defined(OS_WIN)
+bool RenderWidgetHostImpl::CopyFromCompositingSurface(
+    skia::PlatformCanvas* output) {
+  // TODO(mazda): Implement this for other platforms.
+  NOTIMPLEMENTED();
+  return false;
+}
+#endif
+
 #if defined(TOOLKIT_GTK)
 bool RenderWidgetHostImpl::CopyFromBackingStoreToGtkWindow(
     const gfx::Rect& dest_rect, GdkWindow* target) {
   BackingStore* backing_store = GetBackingStore(false);
   if (!backing_store)
     return false;
   (static_cast<BackingStoreGtk*>(backing_store))->PaintToRect(
       dest_rect, target);
   return true;
 }
@@ skipping 1125 matching lines @@
     ui_shim->Send(new AcceleratedSurfaceMsg_BuffersSwappedACK(route_id));
 }
 
 // static
 void RenderWidgetHostImpl::AcknowledgePostSubBuffer(int32 route_id,
                                                     int gpu_host_id) {
   GpuProcessHostUIShim* ui_shim = GpuProcessHostUIShim::FromID(gpu_host_id);
   if (ui_shim)
     ui_shim->Send(new AcceleratedSurfaceMsg_PostSubBufferACK(route_id));
 }