Previously, GtkWindow would add the "app" action group to its own
toplevel muxer.
Change the setup so that GtkApplication creates the toplevel muxer and
adds itself to it as "app". Use this muxer as the parent muxer of any
GtkWindow associated with the application.
This saves a small amount of memory and will allow for accels to be
propagated from the application through to all of the windows.
There are no remaining users of the GtkApplicationWindow API to create
GSimpleActionObserver or to get the GActionObservable (ie: muxer) for
the appwindow. Drop those APIs.
GApplication now makes the session bus and object path available as a
public API on the application instance. Use that instead of trying to
guess values for ourselves.
This causes this version of Gtk+ to depend on GLib 2.32.2, so bumping
version dependency accordingly.
https://bugzilla.gnome.org/show_bug.cgi?id=671249
This is the interface for GtkWidgets that can be associated with an
action on a GtkAppicationWindow or associated GtkApplication.
It essentially features 'action-name' and 'action-target' properties
with some associated convenience API.
This interface is implemented by GtkButton and GtkToolButton.
https://bugzilla.gnome.org/show_bug.cgi?id=667394
