Grab operations are now always taken on the backend connection, and
this breaks GTK+'s event handling.
Instead of taking a grab op, just do the handling ourselves. The
GTK+ connection will get an implicit grab, which means pointer /
keyboard events won't be sent to the rest of mutter, which is good.
Now that we grab devices on the X11 connection, we can run into
cross-connection issues. Since GTK+ frames are on the UI connection,
they'll get the passive grab when we click on them. Forcibly ungrab
on GTK+'s connection before attempting to take a grab on the backend
connection ourselves.
It's been long enough. We can mandate support for these, at least
at build-time. The code doesn't actually compile without either
of these, so just consider that unsupported.
Looking at the code paths where is_mouse / is_keyboard are used,
all of them should never be run when dealing with a COMPOSITOR
grab op, since they're filtered out above or the method is just
never run during that time.
It's confusing that COMPOSITOR is in here, and requires us to
be funny with other places in code, so just take it out.
The idea here is that while we take a WM-side grab, like a compositor
grab or a resizing grab, we need to remove the focus from the Wayland
client.
We make a special exception for CLICKING operations, because these
are really an internal state machine while you're pressing on a button
inside a frame, and in this case, we need to not kill the focus.
A careful analysis of mutter's codebase shows that nothing actually
passes anything but 0 to this. gnome-shell has one instance, but it's
most likely a mistake.
Remove the grab_mask field and the one place in keybindings.c that uses it.
The parameter to begin_grab_op is left in for API compatibility reasons.
Compositors haven't been able to manage more than one screen for
quite a while. Merge MetaCompScreen into MetaCompositor, and update
the API to match.
We still keep MetaScreen in the public compositor API for compatibility
purposes.
We previously separated out MetaDisplay and MetaScreen. mutter
would only manage one screen, but we still kept a list of screens
for simplicity.
With Wayland support, we no longer care about the ability to
manage more than one screen at a time. Remove this by killing
the list of screens, in favor of having just one MetaScreen
in MetaDisplay.
We also kill off active_screen at the same time, since it's
not necessary anymore.
A future cleanup should merge MetaDisplay and MetaScreen. To avoid
breaking API, we should probably keep MetaScreen around as a dummy
type.
display.c is getting a bit crowded. Move most of the handling
out to another file, events.c.
The long-term goal is to have generic event handling here, with
backend-specific handling for the types of windows and such.
If we have a CLICKING grab op we still need to send events to xwayland
so that we get them back for gtk+ to process thus we can't steer
wayland input focus away from it.
https://bugzilla.gnome.org/show_bug.cgi?id=726123
