cc : Stop calculating visible rects on main thread

cc/test/layer_tree_host_common_test.cc

Index: cc/test/layer_tree_host_common_test.cc
diff --git a/cc/test/layer_tree_host_common_test.cc b/cc/test/layer_tree_host_common_test.cc
index 0e277a7ce3a60bd7eed79577c1bcb1146dd483fb..abcdde7cdbc33ecc9e3960942aed1822d33fddb3 100644
--- a/cc/test/layer_tree_host_common_test.cc
+++ b/cc/test/layer_tree_host_common_test.cc
@@ -115,13 +115,19 @@ void LayerTreeHostCommonTestBase::
   gfx::Size device_viewport_size =
       gfx::Size(root_layer->bounds().width() * device_scale_factor,
                 root_layer->bounds().height() * device_scale_factor);
+  PropertyTrees* property_trees =
+      root_layer->layer_tree_host()->property_trees();
+  update_layer_list_.clear();
   draw_property_utils::BuildPropertyTreesAndComputeVisibleRects(
       root_layer, page_scale_layer, inner_viewport_scroll_layer,
       outer_viewport_scroll_layer, overscroll_elasticity_layer,
       elastic_overscroll, page_scale_factor, device_scale_factor,
-      gfx::Rect(device_viewport_size), identity_transform,
-      can_render_to_separate_surface,
-      root_layer->layer_tree_host()->property_trees(), &update_layer_list_);
+      gfx::Rect(device_viewport_size), identity_transform, property_trees);
+  draw_property_utils::Update(root_layer, property_trees,
+                              can_render_to_separate_surface,
+                              &update_layer_list_);
+  draw_property_utils::ComputeVisibleRectsForTesting(
+      property_trees, can_render_to_separate_surface, &update_layer_list_);
 }
 
 void LayerTreeHostCommonTestBase::