Add (or fix) support for Android Wear smartwatch playback controls

[ngseer]

Hello. Recently I've noticed that my Android Wear smartwatch has it's own analogue of the playback controls from the phone's lockscreen. Song name is showing correctly but control itself doesn't work, e.g. tapping on the play/pause button changes it's state on watches (not phone) but has no effect to the app, also the next/previous buttons are missing. I understand that Android Wear support isn't in the features list, but on the other hand Android Wear's widgets and notifications are just a kind of "transparent interface" for the phone's widgets and notifications. Also I've checked several different audioplayers that use lockscreen controls and it works just fine for them. Therefore, I assume that there might be some "standard" way to ensure these controls are working properly on a smartwatch.

[matgras]

I would be very interested in this as well since my speakers and phone are usually upstairs

[ob-tk]

I have the same problem with YotaPhone2 - on the second screen, the name is displayed, but the buttons do not work. It uses standard functions, it works with all audio players except Clementine Remote :(