tests: Remove a spurious #include
tests: Remove a spurious #include

The test-backface-culling has what looks like a stray #include in which
stops the test compiling for backends without GdkPixbuf. Remove it.

http://bugzilla.openedhand.com/show_bug.cgi?id=1867

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