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

content/browser/renderer_host/render_widget_host_impl.cc

Index: content/browser/renderer_host/render_widget_host_impl.cc
diff --git a/content/browser/renderer_host/render_widget_host_impl.cc b/content/browser/renderer_host/render_widget_host_impl.cc
index 2ffb0941f4904d76418a629972dd878487e18442..3afcf5a5628dd9078286d43343df11e387ef4daa 100644
--- a/content/browser/renderer_host/render_widget_host_impl.cc
+++ b/content/browser/renderer_host/render_widget_host_impl.cc
@@ -1778,6 +1778,30 @@ void RenderWidgetHostImpl::AcknowledgePostSubBuffer(int32 route_id,
     ui_shim->Send(new AcceleratedSurfaceMsg_PostSubBufferACK(route_id));
 }
 
+#if defined(USE_AURA)
+// static
+void RenderWidgetHostImpl::AcknowledgeRequestReleaseFront(
+    int request_id,
+    int retry_count,
+    bool was_released,
+    int32 route_id,
+    int gpu_host_id) {
+  GpuProcessHostUIShim* ui_shim = GpuProcessHostUIShim::FromID(gpu_host_id);
+  if (ui_shim)
+    ui_shim->Send(new AcceleratedSurfaceMsg_RequestReleaseFrontACK(
+        route_id, request_id, retry_count, was_released));
+}
+
+// static
+void RenderWidgetHostImpl::SendFrontSurfaceIsProtected(
+    bool is_protected, int32 route_id, int gpu_host_id) {
+  GpuProcessHostUIShim* ui_shim = GpuProcessHostUIShim::FromID(gpu_host_id);
+  if (ui_shim)
+    ui_shim->Send(new AcceleratedSurfaceMsg_SetFrontSurfaceIsProtected(
+        route_id, is_protected));
+}
+#endif
+
 void RenderWidgetHostImpl::DelayedAutoResized() {
   gfx::Size new_size = new_auto_size_;
   // Clear the new_auto_size_ since the empty value is used as a flag to