Play/Pause should always be directed to the last media app that had control

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Install a few media players (Google Listen, Google Music, Tunein
2. Play one of these and hit pause on your bluetooth headset
3. Hit play again media-button-router shows your 3 media players and will 
default to one of them. Let's say Google Listen.
4. Start one of the other media players like say Google Music. Play some music.
5. Hit pause again. Google Music stops playing. Google Music is the last media 
app that had control because it answered to the pause key.
6. Hit play again. Media-button-router again displays the list of 3 media apps. 
Google Listen is "highlighted". If you wait a bit Google Listen will start 
playing.

What is the expected output? What do you see instead?

I expected Google Music, not Google Listen, to start playing. 

What version of the product are you using? 

1.4.0

On what version of android? 

4.0.4

On what device?

Galaxy Nexus

Please provide any additional information below.

I think an option should be provided to "Play/pause last media app"

Oh and thank you, thank you, thank you for making this app. I use bluetooth and 
listen to podcasts and music all the time. When I got my Galaxy Nexus and 
discovered the bluetooth play/pause was being ignored by all media apps I was 
mad. This fixed it for me but I'd like to see the above implemented. If I wish 
to "switch apps" from say Music to Listen to Tunein I can do that manually. But 
more often than not I just want to pause and resume playback on the currently 
running and playing media app.

Original issue reported on code.google.com by adefa...@gmail.com on 2 Jun 2012 at 7:43

[GoogleCodeExporter]

I think, mbr should always ask after pause. So it is possible to change the 
player
without grabbing the phone.
I have this behaviour:
I often listen to podcasts in my car via BT with BeyondPod or AntennaPod.
On work I use Poweramp or Apollo to play music.
Back in my car, and hitting play, the last used (music) player starts directly.
I have to grab the phone and change to a podcast player.

Original comment by mase.set...@gmail.com on 19 May 2014 at 1:39

[GoogleCodeExporter]

Then you always have an interruption whenever you hit play! That's worse! How 
do you change players without grabbing the phone?

Original comment by adefa...@gmail.com on 19 May 2014 at 1:51

[GoogleCodeExporter]

For example I hit play and choose apollo, apollo plays. I hit pause,
apollo stops. I hit play again, mbr should ask me again, what player
to use. So I could switch to antennapod or something without grabbing
the phone. By now, apollo starts playing again. mbr does not ask me
again.

Original comment by mase.set...@gmail.com on 19 May 2014 at 4:37

[GoogleCodeExporter]

Oh I understand what you're asking for. Just seems to me when I think about it 
that more often than not when I hit play I want to play what I was playing 
before, not switch to another app. So, for example, I might be listening to a 
podcast in the car. I might get out to go to a store, waiting in line I'll 
listen to the podcast some more. Get back in the car and I would want to resume 
my podcast. Maybe later I would want to switch to music. Still, in this 
scenario I wanted to play the same stream 3 times vs. 1 time to switch. IMHO 
whatever happens the most frequent should be the default action.

BTW I no longer use this app as I've moved to a Galaxy Note 3 and the Bluetooth 
stuff performs much better, usually restarting what I was last playing. The 
previous phones I had had had (shit 3 hads! That's never happened before!) 
problems with Bluetooth and this app helped. YMMV

Original comment by adefa...@gmail.com on 19 May 2014 at 4:43