Web UI Nuxeo app refresh can lead to `/browseundefined` if there's no current doc

when doing a serial review workflow, user is redirected to http://nuxeo.github.io/nuxeo-web-ui/#!/browseundefined

after validating a task (may he be normal user or administrator)

Note
What seems to be happening is that after a WF is concluded, it will navigate to the previous locations if it is a document, or to an "undefined" browse url if not coming from browse.
Please, see attach animations
In IE, this results in a page refresh (linked ticket)

To reproduce

• create several tasks (not sure it has to be >1)
• go to a unrelated document | home
• open tasks drawer and select a task
• complete task
• => navigates to unrelated document | a browse "undefined" doc url

expected
If coming from task drawer, it show display next task
(in future, all tasks will be only resolved from this area)