+ // List of surfaces to be destroyed, along with what sequences they're still
+ // waiting on.
+ typedef std::list<Surface*> SurfaceDestroyList;
+ SurfaceDestroyList surfaces_to_destroy_;
+
+ // Set of SurfaceSequences that have been satisfied by a frame but not yet
+ // waited on.
+ base::hash_set<SurfaceSequence> satisfied_sequences_;
+