[FIX] web: avoid crash when the Home client action is called without `action` param
[FIX] web: avoid crash when the Home client action is called without `action` param

E.g. this could happen when the HistoryBack client action
was unable to restore the previous breadcrumbs item, and
used the Home action as fallback. Could be reproduce by
performing a successful import from an action without
menu and context, such as what you get after refreshing
your browser.

havt/openerp-web,havt/openerp-web,akretion/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web,akretion/openerp-web,havt/openerp-web