Use the correct root to determinate the webroot for the resource
Use the correct root to determinate the webroot for the resource

Since all the compiled routes are based on the server webroot,
we have to use this, independent from which app this belongs to.

Signed-off-by: Joas Schilling <ab43a7c9cb5b2380afc4ddf8b3e2583169b39a02@schilljs.com>

nextcloud/server,andreas-p/nextcloud-server,nextcloud/server,nextcloud/server,andreas-p/nextcloud-server,andreas-p/nextcloud-server,andreas-p/nextcloud-server,andreas-p/nextcloud-server,nextcloud/server