Command to mark surface inactive, so gpu process can release resources.

content/common/gpu/image_transport_surface_linux.h

 // Copyright (c) 2011 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.
 
 #ifndef CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_LINUX_H_
 #define CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_LINUX_H_
 #pragma once
 
 #if defined(ENABLE_GPU)
 
@@ skipping 20 matching lines @@
 class GLES2Decoder;
 }
 }
 
 class ImageTransportSurface {
  public:
   virtual void OnNewSurfaceACK(
       uint64 surface_id, TransportDIB::Handle surface_handle) = 0;
   virtual void OnBuffersSwappedACK() = 0;
   virtual void OnResize(gfx::Size size) = 0;
+  virtual void OnSurfaceVisible(bool visible) = 0;
 
   // Creates the appropriate surface depending on the GL implementation.
   static scoped_refptr<gfx::GLSurface>
       CreateSurface(GpuChannelManager* manager,
                     int32 render_view_id,
                     int32 renderer_id,
                     int32 command_buffer_id);
 };
 
 class ImageTransportHelper : public IPC::Channel::Listener {
@@ skipping 31 matching lines @@
   gpu::GpuScheduler* Scheduler();
   gpu::gles2::GLES2Decoder* Decoder();
 
   // IPC::Message handlers.
   void OnNewSurfaceACK(uint64 surface_id, TransportDIB::Handle surface_handle);
   void OnBuffersSwappedACK();
 
   // Backbuffer resize callback.
   void Resize(gfx::Size size);
 
+  // Backbuffer visibility changed callback
+  void SurfaceVisible(bool visible);
+
   // Weak pointers that to objects that outlive this helper.
   ImageTransportSurface* surface_;
   GpuChannelManager* manager_;
 
   int32 render_view_id_;
   int32 renderer_id_;
   int32 command_buffer_id_;
   int32 route_id_;
 
   DISALLOW_COPY_AND_ASSIGN(ImageTransportHelper);
 };
 
 #endif  // defined(ENABLE_GPU)
 
 #endif  // CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_LINUX_H_