We don't want to expose the GtkCrossingData struct, and manually
feeding events to event controllers is not something we want to
encourage, going forward.
Add fields for direct descendents to GtkCrossingData,
and populate them when emitting focus change events.
Also add accessors for these fields to GtkEventControllerKey,
and verify that they are set properly in the focus test.
Not done yet: Do the same for pointer crossing events.
Instead of relying on gdk's antiquated crossing events,
create a new GtkCrossingData struct that contains the
actual widgets, and a new event controller vfunc that
expects this struct. This also saves us from making sense
of X's crossing modes and details, and makes for a
generally simpler api.
The ::focus-in and ::focus-out signals of GtkEventControllerKey
have been replaced by a single ::focus-change signal that
takes GtkCrossingData as an argument. All callers have
been updated.
We want to make events readonly, so stop translating
their coordinates and instead pass the translated
coordinates separately, when propagating events.
Remove all the old 2.x and 3.x version annotations.
GTK+ 4 is a new start, and from the perspective of a
GTK+ 4 developer all these APIs have been around since
the beginning.
Event controllers now auto-attach, and the GtkCapturePhase only determines
when are events dispatched, but all controllers are managed by the widget wrt
grabs.
All callers have been updated.
The propagation phase property/methods in GtkEventController are gone,
This is now set directly on the GtkWidget add/remove controller API,
which has been made private.
The only public bit now are the new functions gtk_gesture_attach() and
gtk_gesture_detach() that will use the private API underneath.
All callers have been updated.
