MPVActivity: refactor eventProperty callbacks
MPVActivity: refactor eventProperty callbacks

eventPropertyUi(..) will be executed on the UI thread so there's no need
now to put runOnUiThread everywhere

jeeb/mpv-android,jeeb/mpv-android,jeeb/mpv-android,mpv-android/mpv-android,mpv-android/mpv-android,jeeb/mpv-android,mpv-android/mpv-android,mpv-android/mpv-android,jeeb/mpv-android,mpv-android/mpv-android