[patch][PR10367] Fix the design of GlobalAlias

[Rafael Espíndola]

> The first patch looks good, I'm just opening the second patch.
>
> I think previously you suggested splitting this into GlobalName /
> GlobalValue instead of GlobalValue / GlobalObject.  I kind of liked
> GlobalName.  Any reason to split this way instead?  Does it avoid excessive
> API churn?

Yes. I started going that way, but the churn is so big that it is
probably better if we do that as a separate patch. I will send one
with just the renaming once these are done.

Cheers,
Rafael