TilesFadePlugin: Current behavior is resulting in asynchronous visiblity events

[gkjohnson]

• Can be confirmed in MVTAnnotationPlugin by confirming the visible field is consistent in the callback compared to what has been saved by the plugin.
• Likely relating to Fix tiles fade with displayActiveTiles  #1624

Check for repro in master then after #1624

[gkjohnson]

Likely fixed in #1647 with the traversal fix, which fixed an issue resulting in points