[Feature] Add a Flag for removing media controls button

[B1ack3ye]

As described in issue #1656 in the main repo, the flag #global-media-controls has disappeared from the flags. Would it be possible to reintroduce this flag to disable / hide the button?

I know that, as mentioned in Ahrotahn's comment, you can deactivate this via the launch switches.

It can still be disabled by adding --disable-features=GlobalMediaControls to your launch switches.

I would still consider it a good idea to include this in the flags chrome://flags/ if it is possible.