actor: Pick using the same order as paint
GtkClutterEmbed: Scale allocation by the scale factor

https://bugzilla.gnome.org/show_bug.cgi?id=724055
embed: Pass scaled size back to clutter

Instead of messing with the allocation leave it as is
and send the scaled size to clutter in the synthetic XConfigureEvent.

https://bugzilla.gnome.org/show_bug.cgi?id=724055
Release Clutter-GTK 1.5.2 (snapshot)
Post-release version bump to 1.5.3