xdg-shell: Clarify that geometry doesn't automatically change
The spec says that
When applied, the effective window geometry will be the set
window geometry clamped to the bounding rectangle of the combined
geometry of the surface of the xdg_surface and the associated
subsurfaces.
Thus, a client cannot assume the geometry will adapt to any subsequent changes to any conditions that constrained the geometry.
Signed-off-by: Jonas Ådahl jadahl@gmail.com
NOTE! Enforcing this is will effectively make certain misbehaving Qt applications result in error termination, more specifically obs-studio, which currently has this behavior, where it sets a window geometry, but doesn't attach a buffer, thus ending up with the effective window geometry size 0x0
.