Added alternate way of sending media key presses that allows volume key skip track to work
with Google Play Music.

This is the same function that the lockscreen uses to react to media key presses but
is called via reflection.

See the handleMediaKeyEvent function in:
https://android.googlesource.com/platform/frameworks/base.git/+/android-4.1.1_r1.1/policy/src/com/android/internal/policy/impl/KeyguardViewBase.java
Merge pull request #90 from bparker98/skip-track-fix

Added alternate way of sending media key presses that allows volume key ...