compositor: Add an API to query if the stage is focused
gnome-shell needs to know whether the stage window is focused so
it can synchronize between stage window focus and Clutter key actor
focus. Track all X windows, even those without MetaWindows, when
tracking the focus window, and add a compositor-level API to determine
when the stage is focused.
display: Ensure that we ignore our own focus events for focus predictions
When we set the input focus, we first set the predicted window,
and then try to process focus events. But as XI_FocusOut on the
existing window comes before XI_FocusIn on the new window, we'll
see the focus out on the old window and think the focus is going
to nothing, which makes mutter think the prediction failed.
This didn't really matter as nothing paid attention to the focus
window changing, but with gnome-shell's focus rework, we'll try
and drop keyboard focus in events like these.
Fix this by making sure that we ignore focus window changes of our
own cause when updating the focus window field, by ignoring all
focus events that have a serial the same as the focus request or
lower. Note that if mutter doens't make any requests after the
focus request, this could be racy, as another client could steal
the focus, but mutter would ignore it as the serial was the same.
Bump the serial by making a dummy ChangeProperty request to the
root window in this case.
keybindings: Grab and emit a signal when XK_ISO_Next_Group is pressed
This will make it possible to implement input source switching in
gnome-shell using the popular modifiers-only keybinding that's
implemented on the X server through an XKB option.
keybindings: Add API to freeze/unfreeze the keyboard
We'll use this in gnome-shell to freeze the keyboard right before
switching input source and unfreeze it after that's finished so that
we don't lose any key events to the wrong input source.
prefs: Fix binding remaining grabbed after clearing all strokes
If a binding is updated with a clear set of strokes (effectively
disabling it) we aren't signaling that the binding changed and thus
the previous strokes will continue to be grabbed.
This fixes that and tries to do a better effort at checking if the
binding changed or not.
compositor: Add an API to focus the stage X window
gnome-shell has traditionally just called XSetInputFocus when wanting to
set the input focus to the stage window, but this might cause strange,
hard-to-reproduce bugs because of an interference with mutter's focus
prediction. Add API to allow gnome-shell to focus the stage window that
also updates mutter's internal focus prediction state.
