Revert "Optimistic locking for Issue and Merge Requests" The migration to add `lock_version` in !5146 to every issue and merge request takes too long on GitLab.com since it has to add a default value of 0 to every row. Unfortunately, Rails 4.2 doesn't work properly if the value is left as `nil`; anything using optimistic locking cannot be edited. This bug was fixed in Rails 5.0 via this commit: https://github.com/rails/rails/commit/13772bfa49325a8dc26410d2dcb555665a320f92. I suggest we revert this change for now, and when we upgrade to Rails 5.0 we can reintroduce this feature. See merge request !5245
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
Updated compare dropdowns ## What does this MR do? Removes jQuery autocomplete from compare fields and replaces with GitLabs dropdowns. ## What are the relevant issue numbers? Closes #18891 ## Screenshots (if relevant)  See merge request !4895
This reverts commit c39356998b1850f3dc26fe0b987cb419c1d1afb4.
Add 2FA check to the OAuth authentication mechanism Needed for https://gitlab.com/gitlab-org/gitlab-ce/issues/19312 2FA checks were not being performed when logging in via any of the OAuth providers. Just LDAP had the check. This MR fixes that. See merge request !1976
Make "Get started with Builds" Help Page link work properly
`help_page_path('ci/quick_start', 'README')` causes a link to `https://gitlab.com/help/ci%2Fquick_start/README` which in turn breaks every relative link on the page. This remedies the problem.
That said, this is probably a horrible way of fixing this issue, *but* it does work. I can’t find much information on linking this deeply with Rails routes.
If anyone has suggestions as to a better way of handling this, I'll gladly take them. I tried a few different things, but none of them really worked.
Resolves #14872.
cc: @axil @rspeicher @elstamey
See merge request !3561
Optimize cross ref system notes check ## What does this MR do? This MR optimizes system note visibility checking by memoizing the visible reference count, reducing the overhead of calling `Note#cross_reference_not_visible_for?`. ## Are there points in the code the reviewer needs to double check? Note that since a cross reference message contains, "Mentioned in XYZ", we EXPECT that there is at least one reference. That's why using the ref count > 0 works. ## Why was this MR needed? The previous implementation relied on `Note#cross_reference_not_visible_for?`, which essentially tries to render all the Markdown references in a system note and only displays the note if the user can see the referring project. But this duplicated the work that Banzai::NotesRenderer was doing already. This shaves about 0.8 s from the load time from https://gitlab.com/gitlab-com/operations/issues/42. ## What are the relevant issue numbers? #19273 ## Screenshots (if relevant) ## Does this MR meet the acceptance criteria? - [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added - [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md) - [ ] API support added - Tests - [x] Added for this feature/bug - [x] All builds are passing - [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides) - [x] Branch has no merge conflicts with `master` (if you do - rebase it please) - [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits) See merge request !5070