If 'Search for places?' bottom sheet already visible, don't dismiss and force to re-appear

[mikewilburn]

When panning or zooming to a new extent, the 'Search for places?' bottom sheet notification will appear so that new place search results can be populated that extent.

However, if consecutively panning or zooming to new extents without interacting with the bottom sheet, once the new extent view completes drawing, the alert will auto-collapse and re-expand, which is somewhat of a quirky and unfamiliar behavior.

I propose that if the bottom sheet state is still expanded when the view redraws, the timer to keep the bottom sheet expanded just becomes extended for the an additional ~5 seconds.