[PATCH v5 xdg-shell-unstable-v6] xdg-shell: Add min/max size requests

[Olivier Fourdan]

Hi Mike.

> Okay, if we're not going with uints then at the least can the "use 0 to
> unset min/max" be changed to "use <= 0 to unset min/max" to explicitly
> cover that case?

I think we should simply indicate that the width and height must be greater than or equal to zero, so we remain consistent with the other descriptions (namely set_window_geometry).

Then we could also state that using strictly negative values would raise a protocol error?

Cheers,
Olivier