[pyramid] Fix 404 handling
Avoid seeing a traceback in the UI by catching it before it reaches pyramid and
restore usage of the '404' view.
Closes #16159863
/*
* cubicweb js mock for unit tests
* This module defines variables and functions used in quite a few places
* in cw js framework that can't be used or guessed without a real CW server
*/
var pageid = 'my-page-id';
function _(message) {
return message;
}