Revert "rollout feature flag REAL_NAME_SYSTEM"

related to #772 (closed)

Summary

Revert "rollout feature flag REAL_NAME_SYSTEM".

Some parts like jh/app/controllers/jh/users/terms_controller.rb are not working properly after removing this feature flag without checking whether it's SaaS-only.

What is the current bug behavior?

1. When it's not SaaS
2. Goto http://{{YOUR_HOST}}/-/users/terms
3. You can see the phone validation input is shown on the page

What is the expected correct behavior?

1. When it's not SaaS
2. Goto http://{{YOUR_HOST}}/-/users/terms
3. You should see the phone validation input is NOT shown on the page

Relevant logs and/or screenshots

Now	Expected

Output of checks

Results of GitLab environment info

Expand for output related to GitLab environment info

(For installations with omnibus-gitlab package run and paste the output of:
`sudo gitlab-rake gitlab:env:info`)

(For installations from source run and paste the output of:
`sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production`)

Results of GitLab application Check

Expand for output related to the GitLab application check

(For installations with omnibus-gitlab package run and paste the output of:
sudo gitlab-rake gitlab:check SANITIZE=true)
(For installations from source run and paste the output of:
sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true)
(we will only investigate if the tests are passing)

Possible fixes