HUD: Show first paint invalidation in red

cc/layers/heads_up_display_layer_impl.h

 // 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.
 
 #ifndef CC_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_
 #define CC_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 114 matching lines @@
   ScopedPtrVector<ScopedResource> resources_;
   scoped_ptr<SkCanvas> hud_canvas_;
 
   skia::RefPtr<SkTypeface> typeface_;
 
   Graph fps_graph_;
   Graph paint_time_graph_;
   MemoryHistory::Entry memory_entry_;
   int fade_step_;
   std::vector<DebugRect> paint_rects_;
+  // TODO(kouhei)
+  int fade_step_f_;
+  std::vector<DebugRect> first_paint_rects_;
 
   base::TimeTicks time_of_last_graph_update_;
 
   DISALLOW_COPY_AND_ASSIGN(HeadsUpDisplayLayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_HEADS_UP_DISPLAY_LAYER_IMPL_H_