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

> At least one way springs to mind in which Android can be supported without
> DisplayGroup:
> Implement a "MultiDisplayBuffer" containing multiple displays attached to a
> single DisplayBufferCompositor. That way they are composited together and
> posted together. And the code classes don't need modification.

This is generally what this MP is intended to be, except that multiple displays are attached to the DisplayGroup, instead of having the grouping requirements somewhere in DisplayBufferCompositiors. I guess I'd have to see the MultiDisplayBuffer interface to figure out if android's mm requirements can fit within it.