clear Ambient Cache
Clears the ambient cache data. Ambient cache data is anything not associated with an offline region or a stylepack, including predictively cached data. Use to quickly clear data e.g. for a system update. Note: Do not use this method to clear cache data unless strictly necessary as previously cached data will need to be re-downloaded, leading to increased network usage. If you want general control of the size of the Tile Store @see DiskQuota. This function is blocking the Tile Store until completed.
Parameters
callback
A callback that will be invoked with the result of the cache clearing action.