#FIX: Fixed a bug when renaming content refs.
#FIX: Fixed a bug when renaming content refs.

If some content had been added to the editor, but the type for that
content was missing (not checked in yet/plugin folder not updated
yet etc), the editor would throw a confusing exception. Added a helpful
warning message and a null check.

BraveSirAndrew/duality,abhishekbhalani/duality,Barsonax/duality,ninja2003/duality,caryanne/duality,thecocce/duality,SirePi/duality,RockyTV/duality,AdamsLair/duality,YMRYMR/duality,GHackAnonymous/duality,cpascal/duality,enguard/duality,mfep/duality