Move code setting super type of class Object to null from object.cc to parser.cc

Move code setting super type of class Object to null from object.cc to parser.cc

R=iposva@google.com

Committed: https://code.google.com/p/dart/source/detail?r=23847

[Ivan Posva, 2013-06-11 12:19:05]

LGTM -ip

[regis, 2013-06-11 12:22:08]

Committed patchset #1 manually as r23847 (presubmit successful).

[siva, 2013-06-11 17:05:26]

I guess we still need to retain the multiple check in
Class::NumTypeArguments()

    // Object is its own super class during bootstrap.
    if (cls.super_type() == AbstractType::null() ||
        cls.super_type() == isolate->object_store()->object_type()) {
      break;
    }

Also the comment there does not seem to make sense anymore right.

[regis, 2013-06-12 08:28:39]

On 2013/06/11 17:05:26, siva wrote:
> I guess we still need to retain the multiple check in
> Class::NumTypeArguments()
> 
>     // Object is its own super class during bootstrap.
>     if (cls.super_type() == AbstractType::null() ||
>         cls.super_type() == isolate->object_store()->object_type()) {
>       break;
>     }
> 
> Also the comment there does not seem to make sense anymore right.

Yes, checking for null is still necessary. And I think that a special NoType
instance to avoid a null check would only complicate the code (what is then its
super type?).

An alternative would be to fix the code so that everything works with Object
being its own super class. But here again, this could complicate the code. I
think it is clearer and not too expensive to check for null instead.

The comment has to go. I'll send a cl.

Thanks