[ARC] Do not transfer ARC ownership if the cast is going to result in r-value,
in which case the ownership is redundant. Thanks to John for the suggestion.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143240 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed