Creating a new custom OAuth 2.0 service causes the error message error/invalidpersistenterror to appear.

Steps to reproduce this:

1. Log into the site as an administrator.
2. Browse to Site administration → Server → OAuth 2 services.
3. Click Create new custom service.
4. Enter the following fields:
   1. Name: test
   2. Client ID: test
   3. Client secret: 1234
5. Click Save changes.
6. The red error message error/invalidpersistenterror appears.