Reapply "InstrProf: Update for the LLVM API change in r218879"

Reapplying now that r218887 is in.

This reverts commit r218882, reapplying r218880.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@218888 91177308-0d34-0410-b5e6-96231b3b80d8