HUD: Show first paint invalidation in red

cc/layers/picture_layer.h

Index: cc/layers/picture_layer.h
diff --git a/cc/layers/picture_layer.h b/cc/layers/picture_layer.h
index 80bb4d867a6b01ff5c50a390fb835b0735a3a81a..0b705b9edc37ea23d400868d07f12827ae63af51 100644
--- a/cc/layers/picture_layer.h
+++ b/cc/layers/picture_layer.h
@@ -5,6 +5,8 @@
 #ifndef CC_LAYERS_PICTURE_LAYER_H_
 #define CC_LAYERS_PICTURE_LAYER_H_
 
+#include <vector>
+
 #include "cc/base/invalidation_region.h"
 #include "cc/debug/devtools_instrumentation.h"
 #include "cc/debug/micro_benchmark_controller.h"
@@ -15,7 +17,9 @@
 namespace cc {
 
 class ContentLayerClient;
+class DebugRectHistory;
 class ResourceUpdateQueue;
+struct DebugRect;
 
 class CC_EXPORT PictureLayer : public Layer {
  public:
@@ -58,8 +62,10 @@ class CC_EXPORT PictureLayer : public Layer {
       ScopedLayerObjectTracker instrumentation_object_tracker_;
   // Invalidation to use the next time update is called.
   InvalidationRegion pending_invalidation_;
+  std::vector<DebugRect> debug_invalidation_;
   // Invalidation from the last time update was called.
   Region pile_invalidation_;
+  bool includes_first_paint_invalidation_;
   gfx::Rect last_updated_visible_content_rect_;
   bool is_mask_;