Parsing/Sema for OMPCollapseClause.
Actual usage in Sema for collapsing loops will in some future patch.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@209660 91177308-0d34-0410-b5e6-96231b3b80d8
ASTMatchers.h: Appease msc17.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@209661 91177308-0d34-0410-b5e6-96231b3b80d8