Code review comment for lp://staging/~robertcarr/mir/nested-dont-require-opaque-surface

I don't think opaque is a hard requirement - but is desirable for a desktop session (as we'd like to enable bypass).

The current code is a simplistic POC that got nested running. (Although we're still waiting for some supporting elements - e.g. in Mesa - to land.)

I don't like this approach but, if it is actually useful, don't really mind it landing either.

Going forward I'd prefer to see a mechanism by which the client code can identify an acceptable format for frame buffers.