Add more checks to ClutterContainer::raise() and ::lower()
Add more checks to ClutterContainer::raise() and ::lower()

Check that the actors passed are actually children of the container,
as the implementations assume this.

djdeath/clutter,collects/clutter,spatulasnout/clutter,heysion/clutter-clone,djdeath/clutter,jigpu/clutter,collects/clutter,rkudiyarov/clutter_osx,djdeath/clutter-android,djdeath/clutter-multithreaded,nobled/clutter,jigpu/clutter,djdeath/clutter-multithreaded,djdeath/clutter,ebassi/clutter,spatulasnout/clutter,kerrickstaley/clutter-vala,Distrotech/clutter,Distrotech/clutter,nobled/clutter,Distrotech/clutter,rkudiyarov/clutter_osx,tardyp/clutter,kerrickstaley/clutter-vala,collects/clutter,djdeath/clutter-multithreaded,tardyp/clutter,ebassi/clutter,Distrotech/clutter,heysion/clutter-clone,Distrotech/clutter,ebassi/clutter,collects/clutter,Distrotech/clutter,djdeath/clutter-multithreaded,GNOME/clutter,kerrickstaley/clutter-vala,spatulasnout/clutter,dlespiau/clutter,jigpu/clutter,djdeath/clutter-android,GNOME/clutter,jigpu/clutter,spatulasnout/clutter,GNOME/clutter,spatulasnout/clutter,heysion/clutter-clone,heysion/clutter-clone,nobled/clutter,heysion/clutter-clone,collects/clutter,GNOME/clutter,kerrickstaley/clutter-vala,djdeath/clutter-android,tardyp/clutter,djdeath/clutter-android,ebassi/clutter,jigpu/clutter,rkudiyarov/clutter_osx,GNOME/clutter,ebassi/clutter,djdeath/clutter,dlespiau/clutter,dlespiau/clutter,djdeath/clutter,djdeath/clutter,jigpu/clutter,djdeath/clutter-android,rkudiyarov/clutter_osx