Convert mustash use surface references.

services/ui/surfaces/display_compositor.h

 // Copyright 2015 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 SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_
 #define SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "cc/ipc/display_compositor.mojom.h"
+#include "cc/surfaces/frame_sink_id.h"
 #include "cc/surfaces/surface_manager.h"
 #include "cc/surfaces/surface_observer.h"
 
 namespace cc {
 class SurfaceHittest;
 class SurfaceManager;
 }  // namespace cc
 
 namespace ui {
 
 class DisplayCompositorClient;
 
 // The DisplayCompositor object is an object global to the Window Server app
 // that holds the SurfaceServer and allocates new Surfaces namespaces.
 // This object lives on the main thread of the Window Server.
 // TODO(rjkroege, fsamuel): This object will need to change to support multiple
 // displays.
 class DisplayCompositor : public cc::SurfaceObserver,
                           public base::RefCounted<DisplayCompositor> {
  public:
   explicit DisplayCompositor(cc::mojom::DisplayCompositorClientPtr client);
 
   // TODO(fsamuel):  These methods should be behind a mojo interface.
-  void AddSurfaceReference(const cc::SurfaceId& surface_id,
-                           const cc::SurfaceSequence& surface_sequence);
-  void ReturnSurfaceReferences(const cc::FrameSinkId& frame_sink_id,
-                               const std::vector<uint32_t>& sequences);
+  void AddSurfaceReference(const cc::SurfaceId& parent_id,
+                           const cc::SurfaceId& child_id);
+  void RemoveSurfaceReference(const cc::SurfaceId& parent_id,
+                              const cc::SurfaceId& child_id);
 
   cc::SurfaceManager* manager() { return &manager_; }
 
  private:
   friend class base::RefCounted<DisplayCompositor>;
   virtual ~DisplayCompositor();
 
   // cc::SurfaceObserver implementation.
   void OnSurfaceCreated(const cc::SurfaceId& surface_id,
                         const gfx::Size& frame_size,
                         float device_scale_factor) override;
   void OnSurfaceDamaged(const cc::SurfaceId& surface_id,
                         bool* changed) override;
 
   cc::mojom::DisplayCompositorClientPtr client_;
   cc::SurfaceManager manager_;
 
+  // TODO(fsamuel): Comment on this CL and let me know what ??? below should be,
+  // DisplayCompositorHost or has the name changed?
+  // SurfaceIds that have temporary references from |kRootSurfaceId| so they
+  // aren't GC'd before ??? can add a real reference.
+  std::unordered_map<cc::FrameSinkId,
+                     std::vector<cc::LocalFrameId>,
+                     cc::FrameSinkIdHash>
+      temp_references_;
+
   DISALLOW_COPY_AND_ASSIGN(DisplayCompositor);
 };
 
 }  // namespace ui
 
 #endif  //  SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_