This patch fixes couple of bugs for predefined expression
used inside blocks. It fixes a crash in naming code
for __func__ etc. when used in a block declared globally.
It also brings back old naming convention for
predefined expression which was broken. rdar://18961148


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@222065 91177308-0d34-0410-b5e6-96231b3b80d8