Objective-C ARC. Under ARC, addition of 'bridge' attribute
on CF type is not sufficient and bridge casting is
still required for proper ownership semantics.
// rdar://16650445


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@206910 91177308-0d34-0410-b5e6-96231b3b80d8