Move //sky/compositor to //sky/viewer/compositor

sky/compositor/rasterizer_ganesh.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 SKY_COMPOSITOR_DISPLAY_RASTERIZER_GANESH_H_
-#define SKY_COMPOSITOR_DISPLAY_RASTERIZER_GANESH_H_
-
-#include "sky/compositor/rasterizer.h"
-
-namespace sky {
-class LayerHost;
-
-class RasterizerGanesh : public Rasterizer {
- public:
-  explicit RasterizerGanesh(LayerHost* host);
-  ~RasterizerGanesh() override;
-
-  scoped_ptr<mojo::GLTexture> Rasterize(SkPicture* picture) override;
-
- private:
-  LayerHost* host_;
-
-  DISALLOW_COPY_AND_ASSIGN(RasterizerGanesh);
-};
-
-}  // namespace sky
-
-#endif  // SKY_COMPOSITOR_DISPLAY_RASTERIZER_GANESH_H_