Make RegExp use ToLength on lastIndex when flag is turned on

src/js/macros.py

Index: src/js/macros.py
diff --git a/src/js/macros.py b/src/js/macros.py
index 89502b22183d0ad306988045de7362728ee01bea..0553ca12d16cee0431ac7c4b5fe04bfc656d29ef 100644
--- a/src/js/macros.py
+++ b/src/js/macros.py
@@ -148,6 +148,7 @@ macro TO_INT32(arg) = ((arg) | 0);
 macro TO_UINT32(arg) = ((arg) >>> 0);
 macro TO_LENGTH(arg) = (%ToLength(arg));
 macro TO_LENGTH_OR_UINT32(arg) = (harmony_tolength ? TO_LENGTH(arg) : TO_UINT32(arg));
+macro TO_LENGTH_OR_INTEGER(arg) = (harmony_tolength ? TO_LENGTH(arg) : TO_INTEGER(arg));
 macro TO_STRING(arg) = (%_ToString(arg));
 macro TO_NUMBER(arg) = (%_ToNumber(arg));
 macro TO_OBJECT(arg) = (%_ToObject(arg));