1. Remove `Project#developers_can_push_to_protected_branch?` since it
isn't used anymore.
2. Remove `Project#developers_can_merge_to_protected_branch?` since it
isn't used anymore.
GL dropdowns in issuable form
## What does this MR do?
Changed all the issuable dropdown menus over to user GL dropdowns. This brings the dropdowns to be inline with the issuable filter dropdowns and allows for labels to be created whilst creating/editing an issuable.
## What are the relevant issue numbers?
Closes#12574
## Screenshots (if relevant)
See merge request !4970
Single file diffs
Closes#14103. Related (not part of this MR): #19553.
This adds a `diff_for_path` action to each place we render diffs (commit, compare, new MR, existing MR) which renders the diff for a single path. The action is always available with the same params as the 'parent' action, to make it simpler to generate the URIs.
If a diff is bigger than 10 KB, it will be collapsed by default and have a data attribute added. You can then click the message or the filename to expand that diff. For expanded files, you can collapse and expand them, but they won't make any AJAX requests.

See merge request !4990
Use Gitlab-Workhorse-Send-Data to send entry
## What does this MR do?
Use Gitlab-Workhorse-Send-Data to send entry:
Closes#19224, Closes#19128
Also requires this MR to work:
https://gitlab.com/gitlab-org/gitlab-workhorse/merge_requests/53
## Are there points in the code the reviewer needs to double check?
Do we have a test for this?
## Why was this MR needed?
This way gitlab-workhorse does not have to call any API.
See merge request !5094
Made the search bar on emoji menu sticky
## What does this MR do?
When scrolling down the emoji menu, the search bar disappears. For better UX, the search bar no stays at the top when scrolling.
## Screenshots (if relevant)

See merge request !4743
Rename Code tab to Repository
As discussed in #18830, this renames the "Code" tab to "Repository".
Screenshot now:

See merge request !4807
+ Move 'Edit Project/Group' out of membership-related partial
+ Show the access request buttons only to logged-in users
+ Put the request access buttons out of in a more visible button
+ Improve the copy in the #remove_member_message helper
Signed-off-by: Rémy Coutable <remy@rymai.me>
Fix wiki linking behavior for markdown wiki pages
Related to #18019
- As per the documentation in !4372
## TODO
- [ ] !4432 Have wiki linking behave as per the documentation
- [x] Move `WikiLinkFilter` specs to the pipeline level
- [x] Verify current behavior on wiki `show` page
- [x] Fix current behavior on wiki `show` page
- [x] Verify current behaviour on wiki preview
- [x] Fix current behaviour on wiki preview
- [x] Rewrite all links and get preview links working
- [x] Make sure all links are on-par with the wiki `show` page
- [x] TDD `WikiLinkFilter` and get it working
- [x] Hook `WikiLinkFilter` up
- [x] Fix tests
- [x] Fix `markdown_spec`
- [x] Fix `wiki` spinach feature
- [x] Wait for [build](https://gitlab.com/gitlab-org/gitlab-ce/commit/4f50dd2/builds) to pass
- [x] Make sure all wiki-related pages are working as expected (history, all pages, etc.)
- [x] Test in different ruby versions
- [x] GitLab instances hosted on a relative URL
- [x] Non-markdown rendering formats?
- [x] RDoc
- [x] ASCIIDoc
- [x] Create issues to fix things for RDoc and ASCIIDoc
- [x] Gauge performance impact
- [x] Refactor
- [x] Re-organize commits
- [x] Make sure [build](f860e9a8dc/builds) passes
- [x] Respond to @rymai's comments
- [x] `class WikiLinkFilter < HTML::Pipeline::Filter`
- [x] blank line after guard clause
- [x] keyword arguments for `wiki` and `slug`
- [x] invert the condition
- [x] inline `user` in spec
- [x] Make sure spec names are not out of date
- [x] Comment for each rewrite rule
- [x] Add CHANGELOG entry
- [x] Reorganize commits
- [x] Make sure [build](19b91e749a/builds) passes
- [ ] Wait for merge
See merge request !4432
- Need to pass in a `page_slug` to the filter, so it can rewrite based
on the current page (all links are rewritten to the level of the app root).
- The earlier `markdown_preview` endpoint was at the level of the wiki.
We need to know the current page (for rewriting, as above), so this
commit moves the endpoint to the level of a wiki page.
- Fix all tests
Notifications dropdown on project page now has descriptions
## What does this MR do?
Adds descriptions to the notification settings dropdown on project pages. Also changed the order of them to make more sense.
## What are the relevant issue numbers?
Part of #12758
## Screenshots (if relevant)

See merge request !4374