cc: Add priority rects to tracing.

cc/resources/picture_layer_tiling.cc

Index: cc/resources/picture_layer_tiling.cc
diff --git a/cc/resources/picture_layer_tiling.cc b/cc/resources/picture_layer_tiling.cc
index b52ba9cdf13fbe5b37f85047ebf71b138d48357e..f304a60e30c13e1b884b3ab9bc1129f987e60769 100644
--- a/cc/resources/picture_layer_tiling.cc
+++ b/cc/resources/picture_layer_tiling.cc
@@ -884,6 +884,11 @@ void PictureLayerTiling::AsValueInto(
     base::trace_event::TracedValue* state) const {
   state->SetInteger("num_tiles", tiles_.size());
   state->SetDouble("content_scale", contents_scale_);
+  MathUtil::AddToTracedValue("visible_rect", current_visible_rect_, state);
+  MathUtil::AddToTracedValue("skewport_rect", current_skewport_rect_, state);
+  MathUtil::AddToTracedValue("soon_rect", current_soon_border_rect_, state);
+  MathUtil::AddToTracedValue("eventually_rect", current_eventually_rect_,
+                             state);
   MathUtil::AddToTracedValue("tiling_size", tiling_size(), state);
 }