[flang] Finish cleaning up debug-parser.

Original-commit: flang-compiler/f18@0ef551025ac7cf192e47fad1139ae3381a874b91
Reviewed-on: https://github.com/flang-compiler/f18/pull/66
Tree-same-pre-rewrite: false
diff --git a/flang/lib/parser/parsing.cc b/flang/lib/parser/parsing.cc
index 7ba1c4e..02a9ed5 100644
--- a/flang/lib/parser/parsing.cc
+++ b/flang/lib/parser/parsing.cc
@@ -78,9 +78,11 @@
   log_.Dump(out, cooked_);
 }
 
-void Parsing::Parse() {
+void Parsing::Parse(std::ostream *out) {
   UserState userState{cooked_};
-  userState.set_instrumentedParse(options_.instrumentedParse).set_log(&log_);
+  userState.set_debugOutput(out)
+      .set_instrumentedParse(options_.instrumentedParse)
+      .set_log(&log_);
   ParseState parseState{cooked_};
   parseState.set_inFixedForm(options_.isFixedForm)
       .set_encoding(options_.encoding)