Move JetPlayer to JNI

JetPlayer.cpp was only used by the JetPlayer JNI code, so move
it to the same library.

Test: atest JetPlayerTest
Change-Id: I14b8241c5eb6c789ebc5d6725db716b9b0f8f31f
Merged-In: I14b8241c5eb6c789ebc5d6725db716b9b0f8f31f
3 files changed