Re-land: cc: Use worker context for one-copy tile initialization.

cc/trees/layer_tree_settings.cc

Index: cc/trees/layer_tree_settings.cc
diff --git a/cc/trees/layer_tree_settings.cc b/cc/trees/layer_tree_settings.cc
index 801dc6d77d9172521e7e680b1c99c268596238b9..9d0dcb87020579a2b97313a6d40efb46431dab56 100644
--- a/cc/trees/layer_tree_settings.cc
+++ b/cc/trees/layer_tree_settings.cc
@@ -74,7 +74,8 @@ LayerTreeSettings::LayerTreeSettings()
       gather_pixel_refs(false),
       use_compositor_animation_timelines(false),
       invert_viewport_scroll_order(false),
-      wait_for_beginframe_interval(true) {}
+      wait_for_beginframe_interval(true),
+      max_staging_buffers(32) {}
 
 LayerTreeSettings::~LayerTreeSettings() {}