Completion status standardization for Android auto media

Not sure if it's new or not, but the Android Auto emulator displays an orange dot near never played items when MediaConstants.DESCRIPTION_EXTRAS_KEY_COMPLETION_STATUS is set to MediaConstants.DESCRIPTION_EXTRAS_VALUE_COMPLETION_STATUS_NOT_PLAYED

It was only added for podcast and feel a bit strange to have only podcasts displaying that. This MR standardization this status.

cc @rhstone