Surface Synchronization: Distinguish between dependencies and references

cc/surfaces/surface_dependency_tracker.h

 // Copyright 2017 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_DEPENDENCY_TRACKER_H_
 #define CC_SURFACES_SURFACE_DEPENDENCY_TRACKER_H_
 
 #include "cc/scheduler/begin_frame_source.h"
 #include "cc/surfaces/pending_frame_observer.h"
 #include "cc/surfaces/surface.h"
@@ skipping 32 matching lines @@
   void RequestSurfaceResolution(Surface* surface);
 
   bool has_deadline() const { return frames_since_deadline_set_.has_value(); }
 
   // BeginFrameObserver implementation.
   void OnBeginFrame(const BeginFrameArgs& args) override;
   const BeginFrameArgs& LastUsedBeginFrameArgs() const override;
   void OnBeginFrameSourcePausedChanged(bool paused) override;
 
   // PendingFrameObserver implementation:
-  void OnReferencedSurfacesChanged(
-      Surface* surface,
-      const std::vector<SurfaceId>* active_referenced_surfaces,
-      const std::vector<SurfaceId>* pending_referenced_surfaces) override;
   void OnSurfaceActivated(Surface* surface) override;
   void OnSurfaceDependenciesChanged(
       Surface* surface,
       const SurfaceDependencies& added_dependencies,
       const SurfaceDependencies& removed_dependencies) override;
   void OnSurfaceDiscarded(Surface* surface) override;
 
   // SurfaceObserver implementation:
   void OnSurfaceCreated(const SurfaceInfo& surface_info) override;
   void OnSurfaceDamaged(const SurfaceId& surface_id, bool* changed) override;
@@ skipping 23 matching lines @@
   // The set of SurfaceIds corresponding to observed Surfaces that have
   // blockers.
   base::flat_set<SurfaceId> observed_surfaces_by_id_;
 
   DISALLOW_COPY_AND_ASSIGN(SurfaceDependencyTracker);
 };
 
 }  // namespace cc
 
 #endif  // CC_SURFACES_SURFACE_DEPENDENCY_TRACKER_H_