Dont let messages hit CompositorOutputSurface after it is destroyed.

content/renderer/gpu/compositor_output_surface.cc

Index: content/renderer/gpu/compositor_output_surface.cc
diff --git a/content/renderer/gpu/compositor_output_surface.cc b/content/renderer/gpu/compositor_output_surface.cc
index f0704ffb7c6cf2457fec02bd4771a01fa66f6a18..e50a1e93aa420458328ac9fa3628bb0006a3db65 100644
--- a/content/renderer/gpu/compositor_output_surface.cc
+++ b/content/renderer/gpu/compositor_output_surface.cc
@@ -46,6 +46,7 @@ CompositorOutputSurface::~CompositorOutputSurface() {
   DCHECK(CalledOnValidThread());
   if (!client_)
     return;
+  output_surface_proxy_->ClearOutputSurface();
   output_surface_filter_->RemoveRoute(routing_id_);
 }
 
@@ -66,10 +67,11 @@ bool CompositorOutputSurface::bindToClient(
 
   client_ = client;
 
+  output_surface_proxy_ = new CompositorOutputSurfaceProxy(this);
   output_surface_filter_->AddRoute(
       routing_id_,
-      base::Bind(&CompositorOutputSurface::OnMessageReceived,
-                 base::Unretained(this)));
+      base::Bind(&CompositorOutputSurfaceProxy::OnMessageReceived,
+                 output_surface_proxy_));
 
   return true;
 }