[strong] make --use-strong flag work in d8

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index 953a37519e4ba4b784606d699e2a42c62bbc58c4..7fa6f8c42e68a2cfd9de7f955da93229b94d1283 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -838,7 +838,20 @@ void Shell::AddHistogramSample(void* histogram, int sample) {
 }
 
 
+class NoUseStrongForUtilityScriptScope {
+ public:
+  NoUseStrongForUtilityScriptScope() : flag_(i::FLAG_use_strong) {
+    i::FLAG_use_strong = false;
+  }
+  ~NoUseStrongForUtilityScriptScope() { i::FLAG_use_strong = flag_; }
+
+ private:
+  bool flag_;
+};
+
+
 void Shell::InstallUtilityScript(Isolate* isolate) {
+  NoUseStrongForUtilityScriptScope no_use_strong;
   HandleScope scope(isolate);
   // If we use the utility context, we have to set the security tokens so that
   // utility, evaluation and debug context can all access each other.