Release resources from SurfaceAggregator when new frame arrives.

cc/surfaces/display.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/surfaces/display.h"
 
 #include "base/debug/trace_event.h"
 #include "base/message_loop/message_loop.h"
 #include "cc/debug/benchmark_instrumentation.h"
 #include "cc/output/compositor_frame.h"
@@ skipping 151 matching lines @@
 void Display::CommitVSyncParameters(base::TimeTicks timebase,
                                     base::TimeDelta interval) {
   client_->CommitVSyncParameters(timebase, interval);
 }
 
 void Display::SetMemoryPolicy(const ManagedMemoryPolicy& policy) {
   client_->SetMemoryPolicy(policy);
 }
 
 void Display::OnSurfaceDamaged(SurfaceId surface) {
-  if (aggregator_ && aggregator_->previous_contained_surfaces().count(surface))
+  if (aggregator_ &&
+      aggregator_->previous_contained_surfaces().count(surface)) {
+    aggregator_->ReleaseResources(surface);

[jamesr, 2014/12/13 01:54:26]

it's a little fragile here that we have to make sure we take refs on incoming
resources before notifying the display that it's damaged, or we might release a
resource that we really wanted (iiuc).  I don't really have a great better idea
though.

     client_->DisplayDamaged();
+  }
 }
 
 SurfaceId Display::CurrentSurfaceId() {
   return current_surface_id_;
 }
 
 int Display::GetMaxFramesPending() {
   if (!output_surface_)
     return OutputSurface::DEFAULT_MAX_FRAMES_PENDING;
   return output_surface_->capabilities().max_frames_pending;
 }
 
 }  // namespace cc