Previously the window procedure for the stage window would always
create a ClutterEvent struct for every message and then pass that on
to message_translate to fill in the details. message_translate could
return FALSE to abandon the event. Instead of this, message_translate
now creates and queues the event itself whenever it sees a message
that could translate to an event. The function now returns void. This
has a number of advantages:
* It saves redundantly allocating events for messages that Clutter
doesn't care about.
* A single message can now easily be translated into multiple events.
* There were some messages that were handled and did not fill in the
event struct but did not cause the function to return FALSE. I think
this would end up with a CLUTTER_NOTHING event being emitted.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2135
2c8d73f047