Implement Sebastian's idea for simplifying our handling of the greater-than operator/delimiter. Also, clean up after ourselves following a failed parse of a template-argument-list

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@64166 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index 0f04d13..f7eeef7 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -1112,7 +1112,7 @@
 Parser::ParseParenExpression(ParenParseOption &ExprType,
                              TypeTy *&CastTy, SourceLocation &RParenLoc) {
   assert(Tok.is(tok::l_paren) && "Not a paren expr!");
-  MakeGreaterThanAnOperator G(GreaterThanIsOperator);
+  GreaterThanIsOperatorScope G(GreaterThanIsOperator, true);
   SourceLocation OpenLoc = ConsumeParen();
   OwningExprResult Result(Actions, true);
   CastTy = 0;