Minification breaks serialization

[asturur]

Currently serialization is broken.
While serialization and deserialization may work in the same app on the same build o fabricJS, there is no guarantee it will work across different builds.

Currenty when exporting an object we assign as type the name of the minified variable of the class:

That name is not stable and won't work across differnt builds.

Serialization in the current state is broken

[asturur]

There can't be a release between the fix for #9006 and #9008 because fixing one breaks the other also in the same build