Handlify Object::GetPrototype and (most) callers.

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index 03e52679d8bfb1edffe6d7a4605456dbc04ae44a..da636578f0b7ea16393b8b74acecfe71dced0dc5 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -1033,10 +1033,10 @@ bool Isolate::IsErrorObject(Handle<Object> obj) {
       js_builtins_object(), error_key).ToHandleChecked();
 
   DisallowHeapAllocation no_gc;
-  for (Object* prototype = *obj; !prototype->IsNull();
-       prototype = prototype->GetPrototype(this)) {
+  for (Handle<Object> prototype = obj; !prototype->IsNull();
+       prototype = Object::GetPrototype(this, prototype)) {

[Yang, 2014/04/15 13:10:48]

The DisallowHeapAllocation scope should already make sure that this is safe
without being handlified.

     if (!prototype->IsJSObject()) return false;
-    if (JSObject::cast(prototype)->map()->constructor() ==
+    if (JSObject::cast(*prototype)->map()->constructor() ==
         *error_constructor) {
       return true;
     }