cc: Clarify that color spaces are for raster

cc/test/fake_tile_manager_client.cc

 // 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.
 
 #include "cc/test/fake_tile_manager_client.h"
 
 #include <vector>
 
 namespace cc {
 
 FakeTileManagerClient::FakeTileManagerClient() {
 }
 
 FakeTileManagerClient::~FakeTileManagerClient() {
 }
 
 std::unique_ptr<RasterTilePriorityQueue>
 FakeTileManagerClient::BuildRasterQueue(TreePriority tree_priority,
                                         RasterTilePriorityQueue::Type type) {
   return nullptr;
 }
 
 std::unique_ptr<EvictionTilePriorityQueue>
 FakeTileManagerClient::BuildEvictionQueue(TreePriority tree_priority) {
   return nullptr;
 }
 
-gfx::ColorSpace FakeTileManagerClient::GetTileColorSpace() const {
+gfx::ColorSpace FakeTileManagerClient::GetRasterColorSpace() const {
   return gfx::ColorSpace();
 }
 
 }  // namespace cc