DVCS Quick enabling and disabling repository on UI lead to race condition and may lead to faulty state of repository

Issue Summary

This is reproducible on Data Center: yes

Quick enabling and disabling repository cause that two threads will parallel update statuses of messages connected to this repository. One will be changing state from PENDING → SLEEPING and second one from SLEEPING → PENDING. Updating of statuses is done in loop (not in batch) which leads to race condition. 

Steps to Reproduce

1. Open DVCS admin panel
2. Find repository which has a lot of messages on queue
3. Disable this repository and next enable it again

Expected Results

User shouldn’t be able to enable repository when disabling is not finished. Statuses of messages should be updated in one transaction using batch.

Actual Results

1. Two threads race condition → number of messages in status PENDING and in status SLEEPING is waving
2. Threads can abort after some time and leave repository and its messages in faulty state. See https://jira.atlassian.com/browse/JSWSERVER-21378

Workaround:

Currently there is no known workaround for this behavior. A workaround will be added here when available