[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/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 04c0286..5d780de 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -2304,7 +2304,7 @@
     auto ConstructorCompleter = [&, ThisVarDecl] {
       Actions.CodeCompleteConstructor(
           getCurScope(), ThisVarDecl->getType()->getCanonicalTypeInternal(),
-          ThisDecl->getLocation(), Exprs);
+          ThisDecl->getLocation(), Exprs, T.getOpenLocation());
     };
     if (ThisVarDecl) {
       // ParseExpressionList can sometimes succeed even when ThisDecl is not