Methods get_formview_action can be called by sudo() so for knowing the
real user they should prefer context['uid'] to uid.
Without the action `/web` can't figure out that e.g the view we want is
the one for portal user and not the default one.
With this fix, portal user (not in base.group_user) get to the intended
view with the intended menu when clicking on a invoice/sale order portal
mail link. As for other user there is no change.
closes#10681
opw-666260
Nicolas Lempereur
f5fedbcb18