Return resources immediately after a Surface is destroyed

content/browser/renderer_host/render_widget_host_view_aura_unittest.cc

Index: content/browser/renderer_host/render_widget_host_view_aura_unittest.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_aura_unittest.cc b/content/browser/renderer_host/render_widget_host_view_aura_unittest.cc
index c8af7c661bcb94e34bf37b77f6fa803e15ca25fb..983c77d1c9782cdacf11c7548ef19c4b11cf20b4 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura_unittest.cc
+++ b/content/browser/renderer_host/render_widget_host_view_aura_unittest.cc
@@ -290,6 +290,8 @@ class FakeSurfaceObserver : public cc::SurfaceObserver {
   void OnSurfaceDamaged(const cc::SurfaceId& id, bool* changed) override {
     *changed = true;
   }
+
+  void OnSurfaceDiscarded(const cc::SurfaceId& id) override {}
 };
 
 class FakeFrameSubscriber : public RenderWidgetHostViewFrameSubscriber {