Make LocationEngineImpl public

[zenyagami]

Hello I would like to suggest make LocationEngineImpl in order to implement our own location listener.
Usually this is not needed but in Huawei devices there is a "fused location" in HMS (where google play is not available) so we can take advantage of this, sadly I can't implement my own logic to pass it to the navigation, because LocationEngineImpl it's private, the other option would be add HMS support.
Thanks a lot