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

content/common/gpu/image_transport_surface.cc

Index: content/common/gpu/image_transport_surface.cc
diff --git a/content/common/gpu/image_transport_surface.cc b/content/common/gpu/image_transport_surface.cc
index 7e49b9ff86254fb4aa27de1d16521b6077e3286f..175f8b39c6ca9ea936f03cfcf8a6d71b541d0fa2 100644
--- a/content/common/gpu/image_transport_surface.cc
+++ b/content/common/gpu/image_transport_surface.cc
@@ -96,6 +96,8 @@ bool ImageTransportHelper::OnMessageReceived(const IPC::Message& message) {
                         OnPostSubBufferACK)
     IPC_MESSAGE_HANDLER(AcceleratedSurfaceMsg_NewACK,
                         OnNewSurfaceACK)
+    IPC_MESSAGE_HANDLER(AcceleratedSurfaceMsg_SetFrontSurfaceIsProtected,
+                        OnSetFrontSurfaceIsProtected)
     IPC_MESSAGE_HANDLER(AcceleratedSurfaceMsg_ResizeViewACK, OnResizeViewACK);
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
@@ -201,6 +203,10 @@ void ImageTransportHelper::OnNewSurfaceACK(
   surface_->OnNewSurfaceACK(surface_handle, shm_handle);
 }
 
+void ImageTransportHelper::OnSetFrontSurfaceIsProtected(bool is_protected) {
+  surface_->OnSetFrontSurfaceIsProtected(is_protected);
+}
+
 void ImageTransportHelper::OnBuffersSwappedACK() {
   surface_->OnBuffersSwappedACK();
 }