Simplify code to equivalent code. No need to test for null after cast<>, use
takeAs<> instead of cast<>(.take()). Fix 80-column violation in whitespace after
comment.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191170 91177308-0d34-0410-b5e6-96231b3b80d8