Parsing: Make Parser not know about Isolate during background parsing.

src/background-parsing-task.cc

Index: src/background-parsing-task.cc
diff --git a/src/background-parsing-task.cc b/src/background-parsing-task.cc
index 6ac743e1e52322422eb3190e79879236551496ad..3e153b38f71a3cce6c9fd6b5902f5ba230e087ba 100644
--- a/src/background-parsing-task.cc
+++ b/src/background-parsing-task.cc
@@ -53,7 +53,7 @@ void BackgroundParsingTask::Run() {
   // thread. Passing &parse_info is OK because Parser doesn't store it.
   source_->parser.Reset(new Parser(source_->info.get(), &parse_info));
   source_->parser->set_allow_lazy(source_->allow_lazy);
-  source_->parser->ParseOnBackground();
+  source_->parser->ParseOnBackground(source_->info.get());
 
   if (script_data != NULL) {
     source_->cached_data.Reset(new ScriptCompiler::CachedData(