Move gpu memory calculations to Compositor.

cc/output/output_surface.cc

Index: cc/output/output_surface.cc
diff --git a/cc/output/output_surface.cc b/cc/output/output_surface.cc
index 056879f49d84ba444142101690da109437208d14..423c68a35f32d21b2f350ec5d806e7d5b14c66bf 100644
--- a/cc/output/output_surface.cc
+++ b/cc/output/output_surface.cc
@@ -104,8 +104,6 @@ OutputSurface::~OutputSurface() {
   if (context_provider_.get()) {
     context_provider_->SetLostContextCallback(
         ContextProvider::LostContextCallback());
-    context_provider_->SetMemoryPolicyChangedCallback(
-        ContextProvider::MemoryPolicyChangedCallback());
   }
 }
 
@@ -123,8 +121,6 @@ bool OutputSurface::BindToClient(OutputSurfaceClient* client) {
     if (success) {
       context_provider_->SetLostContextCallback(base::Bind(
           &OutputSurface::DidLoseOutputSurface, base::Unretained(this)));
-      context_provider_->SetMemoryPolicyChangedCallback(
-          base::Bind(&OutputSurface::SetMemoryPolicy, base::Unretained(this)));
     }
   }