Remove a few mutating ObjCCategoryDecl methods.

Remove
  -setClassInterface
  -setNextClassCategory
  -insertNextClassCategory

and combine them in the Create function.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@138817 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed