[CodeComplete] Report location of opening parens for signature help

Summary: Used in clangd.

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: ioeric, kadircet, cfe-commits

Differential Revision: https://reviews.llvm.org/D51436

llvm-svn: 341063
diff --git a/clang/lib/Parse/ParseExpr.cpp b/clang/lib/Parse/ParseExpr.cpp
index d1d8507..39bf1c6 100644
--- a/clang/lib/Parse/ParseExpr.cpp
+++ b/clang/lib/Parse/ParseExpr.cpp
@@ -1650,7 +1650,8 @@
       CommaLocsTy CommaLocs;
 
       if (Tok.is(tok::code_completion)) {
-        Actions.CodeCompleteCall(getCurScope(), LHS.get(), None);
+        Actions.CodeCompleteCall(getCurScope(), LHS.get(), None,
+                                 PT.getOpenLocation());
         cutOffParsing();
         return ExprError();
       }
@@ -1658,8 +1659,9 @@
       if (OpKind == tok::l_paren || !LHS.isInvalid()) {
         if (Tok.isNot(tok::r_paren)) {
           if (ParseExpressionList(ArgExprs, CommaLocs, [&] {
-                Actions.CodeCompleteCall(getCurScope(), LHS.get(), ArgExprs);
-             })) {
+                Actions.CodeCompleteCall(getCurScope(), LHS.get(), ArgExprs,
+                                         PT.getOpenLocation());
+              })) {
             (void)Actions.CorrectDelayedTyposInExpr(LHS);
             LHS = ExprError();
           } else if (LHS.isInvalid()) {