[TIMOB-17148] Android: Support "allowBackground" for Ti.Media.VideoPlayer

   var vidWin = Titanium.UI.createWindow({
       title : 'Video View Demo',
       backgroundColor : '#fff'
   });
   
   var videoPlayer = Titanium.Media.createVideoPlayer({
       top : 2,
       autoplay : true,
       backgroundColor : 'blue',
       allowBackground: true,
       height : 300,
       width : 300,
       mediaControlStyle : Titanium.Media.VIDEO_CONTROL_DEFAULT,
       scalingMode : Titanium.Media.VIDEO_SCALING_ASPECT_FIT
   });
   
   var currentPlaybackTime = 0;
   
   var basicSwitch = Ti.UI.createSwitch({
     titleOn:'On BG',
     titleOff:'Off BG',
     value:true,
     width: 200, height:120
   });
   
   var urlToPlay = 'rtsp://r7---sn-a5m7zu76.c.youtube.com/CiILENy73wIaGQlD0rwH11uU1RMYDSANFEgGUgZ2aWRlb3MM/0/0/0/video.3gp';
   
   videoPlayer.url = urlToPlay;
   vidWin.add(videoPlayer);
   vidWin.add(basicSwitch);
   
   // allowBackground: true on Android allows the 
   // player to keep playing when the app is in the 
   // background.
   var audioPlayer = Ti.Media.createAudioPlayer({ 
       url: urlToPlay,
       allowBackground: true
   });  
   
   vidWin.addEventListener('blur', function() {
   	Ti.API.info('Closing VideoPlayer at Time Played: ' + Math.round(videoPlayer.getCurrentPlaybackTime()) + ' milliseconds');
   	if(basicSwitch.getValue()) {
   		currentPlaybackTime = videoPlayer.getCurrentPlaybackTime();
   		audioPlayer.setTime(currentPlaybackTime);
   		audioPlayer.start();
   	}
   });
   
   vidWin.addEventListener('focus', function() {
   	Ti.API.info('Closing AudioPlayer at Time Played: ' + Math.round(audioPlayer.getTime()) + ' milliseconds');
   	if(basicSwitch.getValue()) {
   		currentPlaybackTime = audioPlayer.getTime();
   	    audioPlayer.stop();
   	    audioPlayer.release();
   		videoPlayer.setCurrentPlaybackTime(currentPlaybackTime);
   	}
   });
   
   audioPlayer.addEventListener('complete', function() {
       Ti.API.info('Audio ended at: ' + Math.round(audioPlayer.getTime()) + ' milliseconds');
   });
   
   vidWin.open();