HUD: Show first paint invalidation in red

cc/layers/layer.h

Index: cc/layers/layer.h
diff --git a/cc/layers/layer.h b/cc/layers/layer.h
index dfbbdf7b6f732d3591cc6852cd262b9e2ced25d7..301afea1e0693fa262bf41dab5e4c1b5be2a5c9b 100644
--- a/cc/layers/layer.h
+++ b/cc/layers/layer.h
@@ -124,6 +124,9 @@ class CC_EXPORT Layer : public base::RefCounted<Layer>,
 
   virtual void SetNeedsDisplayRect(const gfx::RectF& dirty_rect);
   void SetNeedsDisplay() { SetNeedsDisplayRect(gfx::RectF(bounds())); }
+  void SetIncludesFirstPaintInvalidation() {
+    includes_first_paint_invalidation_ = true;
+  }
 
   void SetOpacity(float opacity);
   float opacity() const { return opacity_; }
@@ -533,6 +536,8 @@ class CC_EXPORT Layer : public base::RefCounted<Layer>,
   // Note this rect is in layer space (not content space).
   gfx::RectF update_rect_;
 
+  bool includes_first_paint_invalidation_;
+
   scoped_refptr<Layer> mask_layer_;
 
   int layer_id_;