WIP: Propagate SurfaceID up window tree hierarchy

cc/trees/surface_sequence_generator.h

-// Copyright 2016 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_TREES_SURFACE_SEQUENCE_GENERATOR_H_
-#define CC_TREES_SURFACE_SEQUENCE_GENERATOR_H_
-
-#include <stdint.h>
-
-#include "base/macros.h"
-#include "cc/base/cc_export.h"
-
-namespace cc {
-struct SurfaceSequence;
-
-// Generates unique surface sequences for a surface client id.
-class CC_EXPORT SurfaceSequenceGenerator {
- public:
-  SurfaceSequenceGenerator();
-  ~SurfaceSequenceGenerator();
-
-  void set_surface_client_id(uint32_t client_id) {
-    surface_client_id_ = client_id;
-  }
-
-  SurfaceSequence CreateSurfaceSequence();
-
- private:
-  uint32_t surface_client_id_;
-  uint32_t next_surface_sequence_;
-
-  DISALLOW_COPY_AND_ASSIGN(SurfaceSequenceGenerator);
-};
-
-}  // namespace cc
-
-#endif  // CC_TREES_SURFACE_SEQUENCE_GENERATOR_H_