Drop frontbuffers with ui-use-gpu-process, synchronized with browser, decoupled from backbuffer dro…

content/browser/gpu/gpu_process_host_ui_shim.cc

Index: content/browser/gpu/gpu_process_host_ui_shim.cc
diff --git a/content/browser/gpu/gpu_process_host_ui_shim.cc b/content/browser/gpu/gpu_process_host_ui_shim.cc
index e8cd609a94d835171036b1eabc0aa1e4a903dcd5..dd3e86f7fd5262b7eb56d9b078f3f6a6c2b892ed 100644
--- a/content/browser/gpu/gpu_process_host_ui_shim.cc
+++ b/content/browser/gpu/gpu_process_host_ui_shim.cc
@@ -216,6 +216,8 @@ bool GpuProcessHostUIShim::OnControlMessageReceived(
 #if defined(USE_AURA)
     IPC_MESSAGE_HANDLER(GpuHostMsg_AcceleratedSurfaceRelease,
                         OnAcceleratedSurfaceRelease)
+    IPC_MESSAGE_HANDLER(GpuHostMsg_AcceleratedSurfaceRequestReleaseFront,
+                        OnAcceleratedSurfaceRequestReleaseFront)
 #endif
 
     IPC_MESSAGE_UNHANDLED_ERROR()
@@ -309,7 +311,8 @@ void GpuProcessHostUIShim::OnAcceleratedSurfaceNew(
   TransportDIB::Handle shm_handle = TransportDIB::DefaultHandleValue();
 
   view->AcceleratedSurfaceNew(
-      params.width, params.height, &surface_handle, &shm_handle);
+      params.width, params.height, &surface_handle, &shm_handle,
+      params.route_id, host_id_);
   delayed_send.Cancel();
   Send(new AcceleratedSurfaceMsg_NewACK(
       params.route_id, surface_handle, shm_handle));
@@ -394,4 +397,17 @@ void GpuProcessHostUIShim::OnAcceleratedSurfaceRelease(
   view->AcceleratedSurfaceRelease(params.identifier);
 }
 
+void GpuProcessHostUIShim::OnAcceleratedSurfaceRequestReleaseFront(
+    const GpuHostMsg_AcceleratedSurfaceRequestReleaseFront_Params& params) {
+  RenderWidgetHostViewPort* view = GetRenderWidgetHostViewFromSurfaceID(
+      params.surface_id);
+  if (!view)
+    return;
+  view->AcceleratedSurfaceRequestReleaseFront(params.identifier,
+                                              params.request_id,
+                                              params.retry_count,
+                                              params.route_id,
+                                              host_id_);
+}
+
 #endif