actor: Move underallocation warning to diagnostic mode
actor: Move underallocation warning to diagnostic mode

This should keep down the warning messages — at least for the time
being.

ebassi/clutter,djdeath/clutter,GNOME/clutter,jigpu/clutter,djdeath/clutter,ebassi/clutter,ebassi/clutter,djdeath/clutter-multithreaded,djdeath/clutter-android,heysion/clutter-clone,djdeath/clutter,djdeath/clutter,djdeath/clutter-android,jigpu/clutter,jigpu/clutter,collects/clutter,Distrotech/clutter,jigpu/clutter,djdeath/clutter,djdeath/clutter-android,djdeath/clutter-multithreaded,heysion/clutter-clone,jigpu/clutter,djdeath/clutter-android,collects/clutter,Distrotech/clutter,ebassi/clutter,heysion/clutter-clone,kerrickstaley/clutter-vala,kerrickstaley/clutter-vala,Distrotech/clutter,GNOME/clutter,collects/clutter,heysion/clutter-clone,Distrotech/clutter,kerrickstaley/clutter-vala,GNOME/clutter,GNOME/clutter,kerrickstaley/clutter-vala,Distrotech/clutter,heysion/clutter-clone,GNOME/clutter,djdeath/clutter-android,collects/clutter,djdeath/clutter-multithreaded,collects/clutter,ebassi/clutter,djdeath/clutter-multithreaded,djdeath/clutter,jigpu/clutter,Distrotech/clutter