This rewrites the wl_seat protocol implementation to adhere to the new
design principles.
Effectively, we've been supporting wl_seat v7 so the version was also
bumped from 5 to 7.
The main reason why we have factory methods is that up to some point,
kwayland had its own signal to indicate when globals have to be removed.
Now that all globals add destroy listeners for the wl_display object,
we don't have that signal. Most factory methods are equivalent to doing
new T(display).
Besides adding unnecessary boilerplate code, another reason to get rid
of the factory methods is to reduce the amount of merge conflicts. If
several persons work on implementing wayland protocols at the same time,
sooner or later someone will have to resolve merge conflicts in Display.
libwayland-server allows the wl_display accept client connections on
more than one socket. We currently don't listen on multiple sockets,
but it would be nice if Display supported such operation mode.
One of the most disappointing things when writing autotests is dealing
with a race condition where destructor requests are processed after all
globals have been destroyed.
With this change, the Display object will destroy all clients and their
resources before destroying the wl_display object. The good thing about
doing so is that shut down logic becomes simple. We don't have to assume
that wl_resource objects can outlive their wl_global objects, etc. The
bad thing is that it exposed a couple of pre-existing latent bugs in the
data device and the xdg foreign code.
closesplasma/kwayland-server#2
