User Resource refreshes current authenticated user on every user update

Intro

The REST endpoint for the User CRUD operation: UserResource - .../openmrs/ws/rest/v1/user

It's used by OpenMRS REST clients like system admin OWA UI - the Manage account page - to save modified User data.

Bug

When UserResource is used to save an existing user, the currently authenticated user will have selected login location cleared. Resulting in following flow: change user information, get asked again about login location, go back to manage account, repeat.

Steps

1. Go to: https://demo.openmrs.org/openmrs/ 
2. Login as admin, any location
3. Go to system administration
4. Go to Manage Accounts
5. Open edit for John Smith
6. Open edit for User details
   1. Optionally change anything, but most UIs won't check for changes
7. Click save.
8. Depending on what UI you have:
   1. you may be immediately redirected to the location selection screen
   2. click on Manage Accounts breadcrumb and get redirected to login screen