[Interpreter] Add ForInPrepare runtime function which returns a ObjectTriple.

src/runtime/runtime.cc

Index: src/runtime/runtime.cc
diff --git a/src/runtime/runtime.cc b/src/runtime/runtime.cc
index 90f4e4ce3355ea698f778ac28eaf4ecd63d13363..c532d13b289f376b9e61ef4e9d754464d2137a78 100644
--- a/src/runtime/runtime.cc
+++ b/src/runtime/runtime.cc
@@ -27,6 +27,12 @@ FOR_EACH_INTRINSIC_RETURN_OBJECT(F)
 FOR_EACH_INTRINSIC_RETURN_PAIR(P)
 #undef P
 
+#define T(name, number_of_args, result_size)                         \
+  ObjectTriple Runtime_##name(int args_length, Object** args_object, \
+                              Isolate* isolate);
+FOR_EACH_INTRINSIC_RETURN_TRIPLE(T)
+#undef T
+
 
 #define F(name, number_of_args, result_size)                                  \
   {                                                                           \