question: private static void backupAudioConfig ( ) { if ( null != mRestoreAudioConfigTimer ) { mRestoreAudioConfigTimer . cancel ( ) ; mRestoreAudioConfigTimer = null ; mRestoreAudioConfigTimerMask = null ; } else if ( null == mAudioMode ) { AudioManager audioManager = getAudioManager ( ) ; mAudioMode = audioManager . getMode ( ) ; mIsSpeakerOn = audioManager . isSpeakerphoneOn ( ) ; } }
target:  Back up the current audio config.