actor: Remove some double indirection
actor: Remove some double indirection

Use an intermediate variable to avoid a double indirection when accessing
the instance private data structure.

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