-ms-extensions: Implement __super scope specifier (PR13236).

We build a NestedNameSpecifier that records the CXXRecordDecl in which
__super appeared. Name lookup is performed in all base classes of the
recorded CXXRecordDecl. Use of __super is allowed only inside class and
member function scope.

llvm-svn: 218484
diff --git a/clang/lib/Parse/ParseTentative.cpp b/clang/lib/Parse/ParseTentative.cpp
index 8514af2..1020eef 100644
--- a/clang/lib/Parse/ParseTentative.cpp
+++ b/clang/lib/Parse/ParseTentative.cpp
@@ -1181,6 +1181,7 @@
       return TPResult::False;
   }
     // Fall through.
+  case tok::kw___super:
   case tok::kw_decltype:
     // Annotate typenames and C++ scope specifiers.  If we get one, just
     // recurse to handle whatever we get.