Generate the right opcode for this parse node. bug 349283, r=brendan

js/src/jsparse.c

@@ -3284,6 +3284,7 @@ Statement(JSContext *cx, JSTokenStream *ts, JSTreeContext *tc)
                 return NULL;
 
             pn1->pn_type = TOK_LEXICALSCOPE;
+            pn1->pn_op = JSOP_LEAVEBLOCK;
             pn1->pn_pos = tc->blockNode->pn_pos;
             pn1->pn_atom = atom;
             pn1->pn_expr = tc->blockNode;