Merge branch '50020-fe-allow-email-notifications-to-be-disabled-for-all-users-of-a-group' into 'master'

UI for disabling group/project email notifications

Closes #50020

See merge request gitlab-org/gitlab-ce!30961

(cherry picked from commit 1068483f)

7699a87e UI for disabling group/project email notification
bad143ff Rename canChangeEmailsDisabled to canDisableEmails
38b3f9ec Hide emails_disabled checkbox if disabled in group
5e1fc2f5 Apply suggestion to...
bcd5cee9 Addressed review feedback
d602fc12 Minor fixes for gitlab.pot
1ee32758 Update permissions documentation
43c87103 Vue file prettified
e5ec00ce Apply suggestion to app/views/shared/notifications/_button.html.haml
e2de0db9 Disable the subgroup checkbox
dbd7fcbd Add checked to emails_disabled group settings

Partially addresses #47424.

These are dynamic translations, so has to be marked explicitly using `N_`,
but they are not used in runtime, so can exist in separate file.
https://github.com/grosser/gettext_i18n_rails#unfound-translations-with-rake-gettextfind

allowing override for EE.

Adds a rubocop rule (with autocorrect) to ensure line break after guard clauses.

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6342#note_16132150

Always shows the custom option in the dropdown

This reverts commit 13e37a3e.

This is part of #12758

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

* visiting project will create notification setting if missing
* change notification setting per project even without membership
* use notification settings instead of membership on profile page

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Added Global to the drop downs and updated the label of the button to show the current level instead of `Notifications`

Notification dropdown now shows currently active level, and also shows what the actual value of `global` is, if the project has the notification level set to global.

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>