Remove parts of //cc we aren't using

cc/layers/solid_color_layer.h

-// Copyright 2012 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_SOLID_COLOR_LAYER_H_
-#define CC_LAYERS_SOLID_COLOR_LAYER_H_
-
-#include "cc/base/cc_export.h"
-#include "cc/layers/layer.h"
-
-namespace cc {
-
-// A Layer that renders a solid color. The color is specified by using
-// SetBackgroundColor() on the base class.
-class CC_EXPORT SolidColorLayer : public Layer {
- public:
-  static scoped_refptr<SolidColorLayer> Create();
-
-  scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl) override;
-
-  void SetBackgroundColor(SkColor color) override;
-
- protected:
-  SolidColorLayer();
-
- private:
-  ~SolidColorLayer() override;
-
-  DISALLOW_COPY_AND_ASSIGN(SolidColorLayer);
-};
-
-}  // namespace cc
-#endif  // CC_LAYERS_SOLID_COLOR_LAYER_H_