Fix cluster-fuzz found regression in d8 Workers.

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index e165aa47e020e377c713872c552d255ca7acf2f4..5022d93e11ce5f5fc76ba74f2e89e4d0b9b9fbe7 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -1706,7 +1706,7 @@ void Worker::ExecuteInThread() {
         // First run the script
         Handle<String> file_name = String::NewFromUtf8(isolate, "unnamed");
         Handle<String> source = String::NewFromUtf8(isolate, script_);
-        if (Shell::ExecuteString(isolate, source, file_name, true, true)) {
+        if (Shell::ExecuteString(isolate, source, file_name, false, true)) {
           // Get the message handler
           Handle<Value> onmessage =
               global->Get(String::NewFromUtf8(isolate, "onmessage"));