xwayland: Update output nameLength
At creation, Xwayland uses a generic output name ("XWAYLAND0", etc.) for the XRandR outputs, and later, once the name is known from the Wayland protocols, updates the output names using the actual names from the Wayland compositor.
However, when doing so, it simply updates the string, the "nameLength" isn't updated, so the name passed to the clients might either end up being truncated or contain portions of the previous (initial) output name.
Note, this is using a fixed size buffer initialized with zeros, so this cannot leak any data other than the previous output name, so this is mainly a cosmetic issue.
Update the output's "nameLength" when updating the output name.
Signed-off-by: Olivier Fourdan ofourdan@redhat.com Fixes: 3c07a01c - xwayland: Use xdg-output name for XRandR