cc: Remove low quality mode and cleanup tile versions.

cc/resources/raster_mode.h

-// Copyright 2013 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_RESOURCES_RASTER_MODE_H_
-#define CC_RESOURCES_RASTER_MODE_H_
-
-#include <string>
-
-#include "base/memory/scoped_ptr.h"
-
-namespace base {
-class Value;
-}
-
-namespace cc {
-
-// Note that the order of these matters, from "better" to "worse" in terms of
-// quality.
-enum RasterMode {
-  HIGH_QUALITY_RASTER_MODE = 0,
-  LOW_QUALITY_RASTER_MODE = 1,
-  NUM_RASTER_MODES = 2
-};
-
-std::string RasterModeToString(RasterMode mode);
-
-}  // namespace cc
-
-#endif  // CC_RESOURCES_RASTER_MODE_H_