Revert 171569 as it broke some browser_tests on win_aura.

content/common/gpu/image_transport_surface_linux.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"
 
 #include "content/common/gpu/texture_image_transport_surface.h"
 
 namespace content {
 
 // static
 scoped_refptr<gfx::GLSurface> ImageTransportSurface::CreateSurface(
     GpuChannelManager* manager,
     GpuCommandBufferStub* stub,
     const gfx::GLSurfaceHandle& handle) {
   scoped_refptr<gfx::GLSurface> surface;
   if (!handle.handle) {
     DCHECK(handle.transport);
+    DCHECK(handle.parent_client_id);
     surface = new TextureImageTransportSurface(manager, stub, handle);
   } else {
     surface = gfx::GLSurface::CreateViewGLSurface(false, handle.handle);
     if (!surface.get())
       return NULL;
     surface = new PassThroughImageTransportSurface(manager,
                                                    stub,
                                                    surface.get(),
                                                    handle.transport);
   }
 
   if (surface->Initialize())
     return surface;
   else
     return NULL;
 }
 
 }  // namespace content