Remove unused references to included header files

cc/layers/heads_up_display_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/heads_up_display_layer_impl.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "cc/debug/debug_colors.h"
 #include "cc/debug/frame_rate_counter.h"
 #include "cc/debug/paint_time_counter.h"
 #include "cc/output/begin_frame_args.h"
 #include "cc/output/renderer.h"
 #include "cc/quads/texture_draw_quad.h"
 #include "cc/resources/memory_history.h"
 #include "cc/trees/layer_tree_host_impl.h"
 #include "cc/trees/layer_tree_impl.h"
 #include "skia/ext/platform_canvas.h"
-#include "third_party/khronos/GLES2/gl2.h"
-#include "third_party/khronos/GLES2/gl2ext.h"
-#include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkPaint.h"
 #include "third_party/skia/include/core/SkTypeface.h"
 #include "third_party/skia/include/effects/SkColorMatrixFilter.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/geometry/size_conversions.h"
 #include "ui/gfx/hud_font.h"
 
 namespace cc {
 
@@ skipping 802 matching lines @@
   return "cc::HeadsUpDisplayLayerImpl";
 }
 
 void HeadsUpDisplayLayerImpl::AsValueInto(
     base::trace_event::TracedValue* dict) const {
   LayerImpl::AsValueInto(dict);
   dict->SetString("layer_name", "Heads Up Display Layer");
 }
 
 }  // namespace cc