[counters] Use separate counters for background parsing

src/parsing/preparser.cc

Index: src/parsing/preparser.cc
diff --git a/src/parsing/preparser.cc b/src/parsing/preparser.cc
index 8e5e9ab6525c766804733e3fc4339de452324adf..09761ce8874626c042b6b508239cd515c037fc1f 100644
--- a/src/parsing/preparser.cc
+++ b/src/parsing/preparser.cc
@@ -179,11 +179,14 @@ PreParser::Expression PreParser::ParseFunctionLiteral(
     LanguageMode language_mode, bool* ok) {
   // Function ::
   //   '(' FormalParameterList? ')' '{' FunctionBody '}'
+  const RuntimeCallStats::CounterId counters[2][2] = {
+      {&RuntimeCallStats::PreParseWithVariableResolution,
+       &RuntimeCallStats::PreParseBackgroundWithVariableResolution},
+      {&RuntimeCallStats::PreParseNoVariableResolution,
+       &RuntimeCallStats::PreParseBackgroundNoVariableResolution}};
   RuntimeCallTimerScope runtime_timer(
       runtime_call_stats_,
-      track_unresolved_variables_
-          ? &RuntimeCallStats::PreParseWithVariableResolution
-          : &RuntimeCallStats::PreParseNoVariableResolution);
+      counters[track_unresolved_variables_][parsing_on_main_thread_]);
 
   // Parse function body.
   PreParserStatementList body;