Avoid data race when writing Shell::options.script_executed.

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index 9aeac11bb0a439b59a8933a6b15cdc8f0ac1116f..4a52ca36a343e2cca71471629215603a10a7161e 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -296,7 +296,6 @@ bool Shell::ExecuteString(Isolate* isolate, Local<String> source,
                           bool report_exceptions, SourceType source_type) {
   HandleScope handle_scope(isolate);
   TryCatch try_catch(isolate);
-  options.script_executed = true;
 
   MaybeLocal<Value> maybe_result;
   {
@@ -1427,6 +1426,7 @@ void SourceGroup::Execute(Isolate* isolate) {
       Local<String> source =
           String::NewFromUtf8(isolate, argv_[i + 1], NewStringType::kNormal)
               .ToLocalChecked();
+      Shell::options.script_executed = true;
       if (!Shell::ExecuteString(isolate, source, file_name, false, true)) {
         exception_was_thrown = true;
         break;
@@ -1452,6 +1452,7 @@ void SourceGroup::Execute(Isolate* isolate) {
       printf("Error reading '%s'\n", arg);
       Shell::Exit(1);
     }
+    Shell::options.script_executed = true;
     if (!Shell::ExecuteString(isolate, source, file_name, false, true,
                               source_type)) {
       exception_was_thrown = true;