NASA-AMMOS
TilesRenderer: Consider forcefully evicting tiles until cache is not overfull
Eg if the cache size is changed, or new, higher priority tiles are loaded. Related to #1230.
If tiles are downloaded with a different priority than they are evicted than it's possible that there will be a flicker or "downgrade" when evicting tiles. We also don't want to download tiles if they can't be fit in the cache or will be immediately evicted - so how can we know? This is only an issue when the cache is so full it can't fit tiles that should be visible.
This can be done by removing the "used" check from the cache (and the "loaded" check can be moved to the priority callback) but the fade plugin is not so resilient to having visible tiles being removed and should be revisited.