With owl2, the `el` of components if no longer available. One must use a t-ref instead. However, higher order components don't have their own html element. This was the case of the View component. However, it makes sense for this component to be the owner of the view root element, which was previously owned by the Layout. This commit refactors the View/Layout architecture s.t. the root element is now owned by the View, and simplifies/generalizes the Layout in the process. The Layout is no longer tied to the notion of views, and can thus be used in client actions as well. closes odoo/odoo#85639 Related: odoo/enterprise#24903 Signed-off-by: Aaron Bohy (aab) <aab@odoo.com> Co-authored-by: Michael (mcm) <mcm@odoo.com> Co-authored-by: Samuel Degueldre <sad@odoo.com>