Enqueuing new frames in a Surface should cause Displays to reaggregate it

cc/surfaces/surface_aggregator.h

 // 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.
 
 #ifndef CC_SURFACES_SURFACE_AGGREGATOR_H_
 #define CC_SURFACES_SURFACE_AGGREGATOR_H_
 
 #include <set>
 
 #include "base/containers/hash_tables.h"
@@ skipping 11 matching lines @@
 class ResourceProvider;
 class Surface;
 class SurfaceDrawQuad;
 class SurfaceManager;
 
 class CC_SURFACES_EXPORT SurfaceAggregator {
  public:
   SurfaceAggregator(SurfaceManager* manager, ResourceProvider* provider);
   ~SurfaceAggregator();
 
-  scoped_ptr<CompositorFrame> Aggregate(SurfaceId surface_id);
+  scoped_ptr<CompositorFrame> Aggregate(
+      SurfaceId surface_id,
+      std::set<SurfaceId>* contained_surfaces);
 
  private:
   RenderPass::Id RemapPassId(RenderPass::Id surface_local_pass_id,
                              SurfaceId surface_id);
 
   void HandleSurfaceQuad(const SurfaceDrawQuad* surface_quad,
                          RenderPass* dest_pass);
   void CopySharedQuadState(const SharedQuadState* source_sqs,
                            const gfx::Transform& content_to_target_transform,
                            RenderPass* dest_render_pass);
@@ skipping 22 matching lines @@
 
   // The following state is only valid for the duration of one Aggregate call
   // and is only stored on the class to avoid having to pass through every
   // function call.
 
   // This is the set of surfaces referenced in the aggregation so far, used to
   // detect cycles.
   typedef std::set<SurfaceId> SurfaceSet;
   SurfaceSet referenced_surfaces_;
 
+  // This is the set of surfaces that were used in the last draw.
+  SurfaceSet* contained_surfaces_;
+
   // This is the pass list for the aggregated frame.
   RenderPassList* dest_pass_list_;
 
   // Resource list for the aggregated frame.
   TransferableResourceArray* dest_resource_list_;
 
   DISALLOW_COPY_AND_ASSIGN(SurfaceAggregator);
 };
 
 }  // namespace cc
 
 #endif  // CC_SURFACES_SURFACE_AGGREGATOR_H_