Disappearing map controls and mapbox attribution

[chrabyrd]

Interaction patterns, in varying degrees of simplicity/complexity, can cause the map controls and mapbox attribution to 'disappear' from the map. The buttons are still interactable, but cannot be seen by the end-user.

If the controls have vanished, tapping the map ( or a feature on the map ) will bring them back into view.

Attempts to programmatically hack around this (delayed click/touch, promise-based map resize, re-asserting container dimensions, etc ) have been unsuccessful. If the map is part of a GeoJsonFeatureCollection widget, and the widget is part of a list of other widgets, the map controls never become visible ( see #629 )