HUD: Show first paint invalidation in red

cc/layers/picture_layer.cc

Index: cc/layers/picture_layer.cc
diff --git a/cc/layers/picture_layer.cc b/cc/layers/picture_layer.cc
index d175a57c799feabbdddc124e65ea4ad21cdcc47f..30e7e2d3547ae6be615d97245f60b4e872cbd26d 100644
--- a/cc/layers/picture_layer.cc
+++ b/cc/layers/picture_layer.cc
@@ -5,6 +5,7 @@
 #include "cc/layers/picture_layer.h"
 
 #include "base/auto_reset.h"
+#include "cc/debug/debug_rect_history.h"
 #include "cc/layers/content_layer_client.h"
 #include "cc/layers/picture_layer_impl.h"
 #include "cc/trees/layer_tree_impl.h"
@@ -21,6 +22,8 @@ PictureLayer::PictureLayer(ContentLayerClient* client)
     : client_(client),
       pile_(make_scoped_refptr(new PicturePile())),
       instrumentation_object_tracker_(id()),
+      includes_first_paint_invalidation_(false),
+      is_mask_(false),
       update_source_frame_number_(-1),
       can_use_lcd_text_last_frame_(can_use_lcd_text()) {
 }
@@ -53,6 +56,8 @@ void PictureLayer::PushPropertiesTo(LayerImpl* base_layer) {
   // See PictureLayerImpl::PushPropertiesTo for more details.
   layer_impl->invalidation_.Clear();
   layer_impl->invalidation_.Swap(&pile_invalidation_);
+  layer_impl->debug_invalidation_.clear();
+  layer_impl->debug_invalidation_.swap(debug_invalidation_);
   layer_impl->pile_ = PicturePileImpl::CreateFromOther(pile_.get());
 }
 
@@ -110,6 +115,18 @@ bool PictureLayer::Update(ResourceUpdateQueue* queue,
   pending_invalidation_.Swap(&pile_invalidation_);
   pending_invalidation_.Clear();
 
+  bool is_tracing;
+  TRACE_EVENT_CATEGORY_GROUP_ENABLED(
+      TRACE_DISABLED_BY_DEFAULT("cc.debug") "," TRACE_DISABLED_BY_DEFAULT(
+          "devtools.timeline.layers"),
+      &is_tracing);
+  if (is_tracing || layer_tree_host()->debug_state().ShowHudInfo()) {
+    scoped_refptr<LayerDebugInfo> debug_info = TakeDebugInfo();
+    if (debug_info.get()) {
+      debug_invalidation_ = debug_info->GetInvalidationRects(this);
+    }
+  }
+
   if (layer_tree_host()->settings().record_full_layer) {
     // Workaround for http://crbug.com/235910 - to retain backwards compat
     // the full page content must always be provided in the picture layer.