Properly set function index in CallSite constructor

src/builtins/builtins-callsite.cc

Index: src/builtins/builtins-callsite.cc
diff --git a/src/builtins/builtins-callsite.cc b/src/builtins/builtins-callsite.cc
index 2038f28f680aa215f15d220e44dcc1f6849f2a7a..a5aaff44493b7998e70307aa6767e77cc3e94f71 100644
--- a/src/builtins/builtins-callsite.cc
+++ b/src/builtins/builtins-callsite.cc
@@ -64,7 +64,7 @@ BUILTIN(CallSiteConstructor) {
     Handle<Object> fun_index;
     ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, fun_index,
                                        Object::ToUint32(isolate, fun));

[Yang, 2016/08/01 09:11:46]

I think having the integer conversion in the original JS code was just defensive
programming. Let's instead assert that this is a smi. And assert that
wasm::GetNumberOfFunctions(receiver) is larger than the index.

[jgruber, 2016/08/01 12:04:23]

Done.

-    SET_CALLSITE_PROPERTY(obj, call_site_wasm_func_index_symbol, fun);
+    SET_CALLSITE_PROPERTY(obj, call_site_wasm_func_index_symbol, fun_index);
   } else {
     DCHECK(fun->IsJSFunction());
     SET_CALLSITE_PROPERTY(obj, call_site_receiver_symbol, receiver);