This is an ABI break, hopefully an unimportant one since this signal/vmethod
is barely overridden.
The signal has been added an extra ClutterPaintVolume argument, and has been
given a boolean return value. The recursion to the parents has been taken
out of the default implementation and into the caller, using the returned
boolean parameter to control further propagation.
Passing the ClutterPaintVolume is easier on performance, as we don't need
setting this pointer as gobject data just to retrieve/unset it further
in propagation.
https://bugzilla.gnome.org/show_bug.cgi?id=782344
55d168d01a