Reset view feature code still had remains of initial release (Odoo 9.0).
At that point all the view tree was returned, not only the broken view.
Since it has been fixed in 12.0 and refactored in saas-12.3 with this PR, it
now only takes the broken view as argument, handling multiple views has no
sense anymore.
Thus, this commit remove the (unused) multiple view compatibility.
This commit also add a test to test the refactoring or this feature.
Coming from #32009 (task-1943001)
Romain Derie
479585140c