Provide withNullAsEmptyStringRef impl
Provide withNullAsEmptyStringRef impl

We only see this failure in one file, so I've added a static
implementation there. Should take care of that issue.

rudkx/swift,atrick/swift,gregomni/swift,gregomni/swift,ahoppen/swift,JGiola/swift,apple/swift,ahoppen/swift,roambotics/swift,gregomni/swift,atrick/swift,rudkx/swift,rudkx/swift,benlangmuir/swift,glessard/swift,atrick/swift,ahoppen/swift,atrick/swift,roambotics/swift,atrick/swift,JGiola/swift,benlangmuir/swift,rudkx/swift,benlangmuir/swift,apple/swift,apple/swift,roambotics/swift,gregomni/swift,glessard/swift,gregomni/swift,apple/swift,glessard/swift,glessard/swift,glessard/swift,rudkx/swift,JGiola/swift,ahoppen/swift,benlangmuir/swift,glessard/swift,roambotics/swift,apple/swift,benlangmuir/swift,rudkx/swift,roambotics/swift,atrick/swift,JGiola/swift,ahoppen/swift,apple/swift,ahoppen/swift,JGiola/swift,gregomni/swift,benlangmuir/swift,JGiola/swift,roambotics/swift