Problem: When I create a hosted diffusion repository, before activating the repository, the bare diffusion UI throws an error if I leave the edit page.

Steps to reproduce:

1. Create a new, hosted repository, with lots of great names and stuff.
2. When the UI asks you to 'Activate Now' or continue editing basic info, edit the basic information.
3. Maybe add a description to the repository, and some other stuff (autoclose branches, etc)
4. Without activating the repository, navigate to any other page.
5. Then, navigate back to the repository, e.g. /diffusion/xyz/
6. Where you'd normally see some info (Like Commits Importing or something if it was activated), you see an error: File system entity '/var/phabricator/repos/XXX/' does not exist. For example, just click on the Breadcrumbs in the UI of the edit screen to go to the repository itself. Screenshot attached.

Note: the unresolved setup issues messages are from the most recent upgrade, because all the clustering work is deprecating the notification.* settings, etc. I simply upgraded to make sure it was existing on both the old version and HEAD before reporting.

Note: This bug is not particularly egregious, and most people likely won't hit it very often (because they can just hit back in their browser, or will just hit Activate Repository anyway). But it's kind of ugly in the UI and maybe you want to catalog it for a fix some day.

Workaround: Hit Back in your browser. or just append edit/ to the end of the URL (e.g. /diffusion/2/edit/)

Versions: Latest as of this writing:

phabricator fad9e043c322632a19631412d1eb669e59c0c940 (Thu, Apr 14)
arcanist    737f5c0df976fe2b3178aac6ab7feb3d3621d99e (Sat, Apr 9)
phutil      7a184448aff55465476da0e13477b7e6f3446a14 (Thu, Apr 14)