[FIX] portal, website: login redirection

* migrate website to overriding web_login less (still needed to flag it
  as website-enabled) and use _login_redirect for its login redirection
  override needs
* modify portal and website to not replace / shortcut the redirection
  workflow, so it's possible to override those properly if / as
  necessary

addons/portal/controllers/web.py

@@ -16,7 +16,7 @@ class Home(Home):
 
     def _login_redirect(self, uid, redirect=None):
         if not redirect and not request.env['res.users'].sudo().browse(uid).has_group('base.group_user'):
-            return '/my'
+            redirect = '/my'
         return super(Home, self)._login_redirect(uid, redirect=redirect)
 
     @http.route('/web', type='http', auth="none")

addons/website/controllers/main.py

@@ -95,17 +95,20 @@ class Website(Home):
     # while portal users are redirected to the frontend by default
     # ------------------------------------------------------
 
-    @http.route(website=True, auth="public", sitemap=False)
-    def web_login(self, redirect=None, *args, **kw):
-        response = super(Website, self).web_login(redirect=redirect, *args, **kw)
+    def _login_redirect(self, uid, redirect=None):
+        """ Redirect regular users (employees) to the backend) and others to
+        the frontend
+        """
         if not redirect and request.params['login_success']:
-            if request.env['res.users'].browse(request.uid).has_group('base.group_user'):
+            if request.env['res.users'].browse(uid).has_group('base.group_user'):
                 redirect = b'/web?' + request.httprequest.query_string
             else:
                 redirect = '/my'
-            return http.redirect_with_hash(redirect)
-        return response
+        return super()._login_redirect(uid, redirect=redirect)
 
+    @http.route(website=True, auth="public", sitemap=False)
+    def web_login(self, *args, **kw):
+        return super().web_login(*args, **kw)
     # ------------------------------------------------------
     # Business
     # ------------------------------------------------------