cc: Remove code for drawing checkerboard quads, it's not used.

cc/layers/picture_layer_impl.cc

 // 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.
 
 #include "cc/layers/picture_layer_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <set>
 
 #include "base/time/time.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "cc/base/math_util.h"
 #include "cc/debug/debug_colors.h"
 #include "cc/debug/micro_benchmark_impl.h"
 #include "cc/debug/traced_value.h"
 #include "cc/layers/append_quads_data.h"
 #include "cc/layers/solid_color_layer_impl.h"
 #include "cc/output/begin_frame_args.h"
-#include "cc/quads/checkerboard_draw_quad.h"
 #include "cc/quads/debug_border_draw_quad.h"
 #include "cc/quads/picture_draw_quad.h"
 #include "cc/quads/solid_color_draw_quad.h"
 #include "cc/quads/tile_draw_quad.h"
 #include "cc/tiles/tile_manager.h"
 #include "cc/tiles/tiling_set_raster_queue_all.h"
 #include "cc/trees/layer_tree_impl.h"
 #include "cc/trees/occlusion.h"
 #include "ui/gfx/geometry/quad_f.h"
 #include "ui/gfx/geometry/rect_conversions.h"
@@ skipping 1185 matching lines @@
 
 bool PictureLayerImpl::IsOnActiveOrPendingTree() const {
   return !layer_tree_impl()->IsRecycleTree();
 }
 
 bool PictureLayerImpl::HasValidTilePriorities() const {
   return IsOnActiveOrPendingTree() && IsDrawnRenderSurfaceLayerListMember();
 }
 
 }  // namespace cc