Add/remove surface references via MojoCompositorFrameSink.

cc/surfaces/surface_manager.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_MANAGER_H_
 #define CC_SURFACES_SURFACE_MANAGER_H_
 
 #include <stdint.h>
 
 #include <list>
@@ skipping 85 matching lines @@
 
   // Register a relationship between two namespaces.  This relationship means
   // that surfaces from the child namespace will be displayed in the parent.
   // Children are allowed to use any begin frame source that their parent can
   // use.
   void RegisterFrameSinkHierarchy(const FrameSinkId& parent_frame_sink_id,
                                   const FrameSinkId& child_frame_sink_id);
   void UnregisterFrameSinkHierarchy(const FrameSinkId& parent_frame_sink_id,
                                     const FrameSinkId& child_frame_sink_id);
 
+  void PrintReferenceTree(const std::string& name);
+
   // SurfaceReferenceManager:
   const SurfaceId& GetRootSurfaceId() const override;
   void AddSurfaceReference(const SurfaceId& parent_id,
                            const SurfaceId& child_id) override;
   void RemoveSurfaceReference(const SurfaceId& parent_id,
                               const SurfaceId& child_id) override;
   size_t GetSurfaceReferenceCount(const SurfaceId& surface_id) const override;
   size_t GetReferencedSurfaceCount(const SurfaceId& surface_id) const override;
 
  private:
+  void PrintReferenceTreeImpl(const SurfaceId& surface_id,
+                              std::string indent,
+                              std::string* str);
+
   void RecursivelyAttachBeginFrameSource(const FrameSinkId& frame_sink_id,
                                          BeginFrameSource* source);
   void RecursivelyDetachBeginFrameSource(const FrameSinkId& frame_sink_id,
                                          BeginFrameSource* source);
   // Returns true if |child namespace| is or has |search_frame_sink_id| as a
   // child.
   bool ChildContains(const FrameSinkId& child_frame_sink_id,
                      const FrameSinkId& search_frame_sink_id) const;
 
   void GarbageCollectSurfaces();
@@ skipping 50 matching lines @@
   std::unordered_map<SurfaceId, SurfaceIdSet, SurfaceIdHash>
       parent_to_child_refs_;
 
   // Set of which sources are registered to which namespace.  Any child
   // that is implicitly using this namespace must be reachable by the
   // parent in the dag.
   std::unordered_map<BeginFrameSource*, FrameSinkId> registered_sources_;
 
   // Root SurfaceId that references display root surfaces. There is no Surface
   // with this id, it's for bookkeeping purposes only.
-  const SurfaceId kRootSurfaceId;
+  const SurfaceId root_surface_id_;
 
   DISALLOW_COPY_AND_ASSIGN(SurfaceManager);
 };
 
 }  // namespace cc
 
 #endif  // CC_SURFACES_SURFACE_MANAGER_H_