Code review comment for lp:~kdub/mir/display-groups

I'd rather see a "MultiDisplayBuffer" or "EverythingDisplayBuffer" that composites multiple outputs together with a single "post" for Android. Then DisplayBufferCompositor doesn't have to change.

The currently proposed design isn't just undesirable for mesa/DRM, but undesirable for any raw platform that flips/blits on post. All our future platforms will also want to avoid DisplayGroups so that the non-primary monitors don't tear or skip frames. So I think it's a better idea to invest in making this more clearly Android-specific.

I can only imagine this works at all on Android without tearing or skipping (does it?) if Android is abstracting and asynchronously deferring the page flipping in the background.