Native Android Mediaplayer on Galaxy Note 4

I looked into the low performance and discovered my optimizes were dropped out of the 4.11 branch by mistake during an integration. I’ve added them back in along with my fixes for SetRate. You can find these in this GitHub commit: https://github.com/EpicGames/UnrealEngine/commit/b151006b20094a34002a4f814b12d5a116c88fe8