browse/origin-search: Percent encode ? character only in origin URL
When an origin URL is provided as URL argument to a Web API call performed by XHR, only percent encode the '?' character as using encodeURIComponent results in a 404 error in production and staging otherwise (maybe a side effect of Varnish cache).
Related to #4675 (closed)
Migrated from D8826 (view on Phabricator)