Enables compositing support for webview.

content/common/gpu/image_transport_surface_win.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/common/gpu/image_transport_surface.h"
 
 // Out of order because it has conflicts with other includes on Windows.
 #include "third_party/angle/include/EGL/egl.h"
 
 #include "base/bind.h"
@@ skipping 228 matching lines @@
     GpuChannelManager* manager,
     GpuCommandBufferStub* stub,
     const gfx::GLSurfaceHandle& handle) {
   scoped_refptr<gfx::GLSurface> surface;
 
   if (!handle.handle) {
     // If we don't have a valid handle with the transport flag set, then we're
     // coming from a renderer and we want to render the webpage contents to a
     // texture.
     DCHECK(handle.transport);
-    DCHECK(handle.parent_client_id);
     surface = new TextureImageTransportSurface(manager, stub, handle);
   } else {
     if (gfx::GetGLImplementation() == gfx::kGLImplementationEGLGLES2 &&
         !CommandLine::ForCurrentProcess()->HasSwitch(
             switches::kDisableImageTransportSurface)) {
       // This path handles two different cases.
       //
       // For post-Vista regular Windows, this surface will be used for
       // renderer compositors.
       //
@@ skipping 20 matching lines @@
     }
   }
 
   if (surface->Initialize())
     return surface;
   else
     return NULL;
 }
 
 }  // namespace content