Add a simple compositor for Sky

sky/compositor/surface_allocator.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 SKY_COMPOSITOR_SURFACE_ALLOCATOR_H_
+#define SKY_COMPOSITOR_SURFACE_ALLOCATOR_H_
+
+#include "base/basictypes.h"
+
+namespace sky {
+
+class SurfaceAllocator {
+ public:
+  SurfaceAllocator(uint32_t id_namespace);
+  ~SurfaceAllocator();
+
+  uint64_t CreateSurfaceId();
+
+ private:
+  uint32_t id_namespace_;
+  uint32_t next_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(SurfaceAllocator);
+};
+
+}  // namespace sky
+
+#endif  // SKY_COMPOSITOR_SURFACE_ALLOCATOR_H_