Remove parts of //cc we aren't using

cc/layers/content_layer.h

-// Copyright 2010 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_LAYERS_CONTENT_LAYER_H_
-#define CC_LAYERS_CONTENT_LAYER_H_
-
-#include "base/basictypes.h"
-#include "cc/base/cc_export.h"
-#include "cc/layers/tiled_layer.h"
-#include "cc/resources/layer_painter.h"
-
-class SkCanvas;
-
-namespace cc {
-
-class ContentLayerClient;
-class ContentLayerUpdater;
-
-class CC_EXPORT ContentLayerPainter : public LayerPainter {
- public:
-  static scoped_ptr<ContentLayerPainter> Create(ContentLayerClient* client);
-
-  void Paint(SkCanvas* canvas, const gfx::Rect& content_rect) override;
-
- private:
-  explicit ContentLayerPainter(ContentLayerClient* client);
-
-  ContentLayerClient* client_;
-
-  DISALLOW_COPY_AND_ASSIGN(ContentLayerPainter);
-};
-
-// A layer that renders its contents into an SkCanvas.
-class CC_EXPORT ContentLayer : public TiledLayer {
- public:
-  static scoped_refptr<ContentLayer> Create(ContentLayerClient* client);
-
-  void ClearClient();
-
-  void SetLayerTreeHost(LayerTreeHost* layer_tree_host) override;
-  void SetTexturePriorities(const PriorityCalculator& priority_calc) override;
-  bool Update(ResourceUpdateQueue* queue,
-              const OcclusionTracker<Layer>* occlusion) override;
-  bool NeedMoreUpdates() override;
-
-  void SetContentsOpaque(bool contents_opaque) override;
-
-  skia::RefPtr<SkPicture> GetPicture() const override;
-
-  void OnOutputSurfaceCreated() override;
-
- protected:
-  explicit ContentLayer(ContentLayerClient* client);
-  ~ContentLayer() override;
-
-  bool HasDrawableContent() const override;
-
-  // TiledLayer implementation.
-  LayerUpdater* Updater() const override;
-
- private:
-  // TiledLayer implementation.
-  void CreateUpdaterIfNeeded() override;
-
-  ContentLayerClient* client_;
-  scoped_refptr<ContentLayerUpdater> updater_;
-
-  DISALLOW_COPY_AND_ASSIGN(ContentLayer);
-};
-
-}  // namespace cc
-#endif  // CC_LAYERS_CONTENT_LAYER_H_