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

cc/quads/checkerboard_draw_quad.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/quads/checkerboard_draw_quad.h"
-
-#include "base/logging.h"
-#include "base/trace_event/trace_event_argument.h"
-#include "base/values.h"
-
-namespace cc {
-
-CheckerboardDrawQuad::CheckerboardDrawQuad() : color(0), scale(0.f) {
-}
-
-void CheckerboardDrawQuad::SetNew(const SharedQuadState* shared_quad_state,
-                                  const gfx::Rect& rect,
-                                  const gfx::Rect& visible_rect,
-                                  SkColor color,
-                                  float scale) {
-  gfx::Rect opaque_rect = SkColorGetA(color) == 255 ? rect : gfx::Rect();
-  bool needs_blending = false;
-  DrawQuad::SetAll(shared_quad_state, DrawQuad::CHECKERBOARD, rect, opaque_rect,
-                   visible_rect, needs_blending);
-  this->color = color;
-  this->scale = scale;
-}
-
-void CheckerboardDrawQuad::SetAll(const SharedQuadState* shared_quad_state,
-                                  const gfx::Rect& rect,
-                                  const gfx::Rect& opaque_rect,
-                                  const gfx::Rect& visible_rect,
-                                  bool needs_blending,
-                                  SkColor color,
-                                  float scale) {
-  DrawQuad::SetAll(shared_quad_state, DrawQuad::CHECKERBOARD, rect, opaque_rect,
-                   visible_rect, needs_blending);
-  this->color = color;
-  this->scale = scale;
-}
-
-const CheckerboardDrawQuad* CheckerboardDrawQuad::MaterialCast(
-    const DrawQuad* quad) {
-  DCHECK(quad->material == DrawQuad::CHECKERBOARD);
-  return static_cast<const CheckerboardDrawQuad*>(quad);
-}
-
-void CheckerboardDrawQuad::ExtendValue(
-    base::trace_event::TracedValue* value) const {
-  value->SetInteger("color", color);
-  value->SetDouble("scale", scale);
-}
-
-}  // namespace cc