This reverts a regression in ed5438fc21
which set `tileZoom = idealZoom` for all types of tiles.
The second change makes it so that panTiles get loaded only if they have
a lower *data zoom* (only if they cover a larger area).
This reverts a regression in ed5438fc21
which set `tileZoom = idealZoom` for all types of tiles.
The second change makes it so that panTiles get loaded only if they have
a lower *data zoom* (only if they cover a larger area).