[Seaside] [2.8] isolate: not working properly

[radoslav hodnicak]

breaking isolate: doesn't return to the active (isolated) component.

tried with Seaside2.8a1-pmm.411 in Squeak3.9:

open the sushi store example
add something to the cart
proceed to checkout until you get the address form
use the browser back button to get back to items for sale
try to add something to the cart

- you get two page expired redirects and then an empty page. what you 
should get is the address form again.

rado