WIP: squash! st/mesa: Replace UsesStreams by ActiveStreamMask for GS
@lfrb: Seems this was a slip-up in that commit. I'm not 100% sure about what exact type is best here, but this does the trick at least.
@lfrb: Seems this was a slip-up in that commit. I'm not 100% sure about what exact type is best here, but this does the trick at least.