ESLint config: https://github.com/airbnb/javascript

Remove use of wait_for_ajax since jQuery was removed

Fixes #23812

See merge request !7111

Replace jquery-cookie plugin with js-cookie

## What does this MR do?

Removes an outdated and unmaintained dependency [jquery.cookie](https://github.com/carhartl/jquery-cookie) with its successor [js.cookie](https://github.com/js-cookie/js-cookie) which is not dependent on jQuery.

Also this MR adds a global default cookie `path` setting which defaults to the GitLab root directory.  Now, setting a cookie to any path other than `gon.relative_url_root` requires an explicit opt-out.  This is a sensible default and should prevent accidental omission going forward.

## Are there points in the code the reviewer needs to double check?

Double check that all instances of `$.cookie(x)` have been replaced by `Cookies.get(x)` and all instances of `$.cookie(x, y, z)` are replaced with `Cookies.set(x, y, z)`.  All javascripts which set or retrieve cookie values should function just as before.

## Why was this MR needed?

One more step toward shaking off jQuery as a dependency (#23022), also [jquery.cookie](https://github.com/carhartl/jquery-cookie) is no longer maintained and hasn't seen an update in 2+ years.

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG.md) entry added
- Tests
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [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 it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

#23022

See merge request !7085

Fixes #23812

Specify which Fog storage drivers are imported by default in backup_restore.md

Replaces https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5783

See merge request !7108

Specify which Fog storage drivers are imported by default in backup_restore.md

Replaces https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5783

See merge request !7072

Make issues search less finicky

## What does this MR do?

1. Tracks issues search pristine-ness, to ignore non-mutating keyups.
2. Increase debounce wait on issues search execution from 500ms to 1000ms.
3. Ensures issues search retains focus after search execution

Note: Issues search is being overhauled (https://gitlab.com/gitlab-org/gitlab-ce/issues/21747), so most (if not all) of these changes will no longer be used. But given that the overhaul has been pushed back a release (8.14?), it makes sense to do some quick fixes to improve UX in the meantime.

## Are there points in the code the reviewer needs to double check?

Will adding autofocus to the search input create unforeseen problems?

## Why was this MR needed?

- At the moment, issues search is run on any keyup, even if search terms remain the same. This is an oversight that is both a tax on servers and an annoyance to users. 

- Searches are executed pretty quickly after a gap in keyups. It's too fast according to internal and enterprise customer feedback.

- Focus is lost when a search is conducted, so you have to either tab to (any sane person would not do this, given our tab order) or reach for the mouse and select the input again. 

These are all pretty heavily complained about issues that are, to quote community users, "rage-inducing" and "major accessibility issue[s]".

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] API support added
- Tests
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [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)

## What are the relevant issue numbers?

https://gitlab.com/gitlab-org/gitlab-ce/issues/21503
https://gitlab.com/gitlab-org/gitlab-ce/issues/21984
https://gitlab.com/gitlab-org/gitlab-ce/issues/21597

See merge request !6735

Fix the `migration paths` CI job

## What does this MR do?

It fixes the `migration paths` CI job. This job started failing at the time we added a migration that is actually using Redis.

The issue was that the `config/resque.yml` file we're using is not back-compatible with the `v8.5.9` version we're checking out in the first part of the job, that's why we're using a UNIX socket for this version.

To fix the issue:

* We use 'SETUP_DB: 'false'` in the job variables to speed up the job (it does not make sense to run migration before checking out v8.5.9)
* We just copy config/resque.yml.example to config/resque.yml at is simply has correct structure when checked out from v8.5.9
* When we revert to CI_BUILD_REF, we run prepare script again, which swaps config/resque.yml again, using new version this time.

Fixes #23658.

Note: the `migration paths` CI job is run on `master` only but you can see a successful build here: https://gitlab.com/gitlab-org/gitlab-ce/commit/fd99ec1a8ecc49ef70c4358ca7be2987f2a7505f

See merge request !7092

Fix events order in users/:id/events endpoint

## What does this MR do?

Order of events in contributions API is currently being lost, though docs are saying:

> Get the contribution events for the specified user, sorted **from newest to oldest**.

Order becomes different after `.merge(ProjectsFinder.new.execute(current_user))` call, so I moved ordering below this line.

This MR also removes extra `.page(params[:page])` call in the method chain, since [`paginate(events)` already does it](https://gitlab.com/airat/gitlab-ce/blob/master/lib/api/helpers.rb#L112).

See merge request !7039

Don't schedule ProjectCacheWorker unless needed

## What does this MR do?

This MR changes `ProjectCacheWorker.perform_async` so scheduling only takes place when needed. See the commits for more details.

See merge request !7099

Reduce overhead of LabelFinder by avoiding #presence call

Some users experienced 502 timeouts when viewing group labels.
Labels#open_issues_count and Label#open_merge_requests_count were
taking a long time to load because they were loading every ActiveRecord
of the user-accessible projects into memory. This change modifies so
that only the IDs are loaded into memory.

Closes #23684

See merge request !7094

This will change the update process to checkout gitlab-shell version 3.6.6 instead of 3.6.3 as currently described in the update document

See merge request !6976

Stop appending templates - Temporary fix

## What does this MR do?

This is the temporary fix for #23315. This stops the templates appending to any existing text.

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

Temporary fix for #23315.

## Screenshots (if relevant)

![2016-10-21_21.58.55](/uploads/ba54d89fcb2fb9cf99ff24c8623ae413/2016-10-21_21.58.55.gif)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG.md) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

See merge request !7050

Tidied up pipelines.js.es6 and removed jQuery where acceptable.

## What does this MR do?

A week or so ago, I made some changes to `pipeline.js` as it was a single function and we now needed to expand on the JS logic for pipelines. I decided to turn it into `class Pipelines` of `pipelines.js.es6`. To avoid review confusion I held back from changing the pre-existing function so it dealt with instance members. Every time you click the button it would re-query all the elements it needed, now its a class it doesn't need that as we can store the required elements on construction.

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [ ] [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
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

See merge request !6950

Close any open tooltips before page:fetch

## What does this MR do?

Resolve #22743 by removing any open tooltips before `page:fetch`.

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

Open tooltips were never closed (could never be) in certain browsers after navigating with Turbolinks and going back.

## 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
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?


Closes #22743

See merge request !6795

Add an API styleguide

This adds a styleguide for API development. Spinned-of from https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6860#note_16922017.

[ci skip]

See merge request !6864

Adds test for feature in this MR https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6720

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6720

See merge request !6854

This changes ProjectCacheWorker.perform_async so it only schedules a job
when no lease for the given project is present. This ensures we don't
end up scheduling hundreds of jobs when they won't be executed anyway.

Some users experienced 502 timeouts when viewing group labels.
Labels#open_issues_count and Label#open_merge_requests_count were
taking a long time to load because they were loading every ActiveRecord
of the user-accessible projects into memory. This change modifies the system
so that #presence and hence to_a isn't called.

Closes #23684

Enable SingleLinePerSelector in scss-lint

## What does this MR do?
Enables `SingleLinePerSelector` in `.scss-lint.yml`

## Are there points in the code the reviewer needs to double check?
This MR touches a lot of files, just need another pair of eyes to look through and make sure I didn't break anything.

## Why was this MR needed?
Improve SCSS maintainability and consistency

## Screenshots (if relevant)
None

## Does this MR meet the acceptance criteria?

- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [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 it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
#23485

See merge request !7081

Stop unauthorized users dragging on issue boards

Closes #23763

See merge request !7096

Closes #23763

Change the approach to check if patches apply cleanly

Closes #23372

See merge request !6949

Show commits from source project. Be consistent with pipeline

## What does this MR do?

Show commits from source project instead of target project.

## Why was this MR needed?

To be consistent.

## 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)
- Tests
  - [x] Added for this feature/bug

## What are the relevant issue numbers?

Closes #3596

See merge request !6658

Fix branch protection API.

## What does this MR do?

- Fixes the branch protection API.
- Closes #21513 
- EE Merge Request: gitlab-org/gitlab-ee!718

## Tasks

- [ ]  #21513 !6215 Protected branches API bug
    - [x]  Investigate
    - [x]  Test + Fix
    - [x]  Changelog
    - [x]  MR
    - [x]  Wait for build to pass
    - [x]  Review
    - [x]  Check for EE conflicts
    - [x]  Create EE MR
    - [x]  Refactor + Fix
    - [x]  Rebase EE MR against EE master
    - [x]  Wait for builds to pass
    - [x]  Assign to dbalexandre/douwe
    - [x]  Implement latest review comments
    - [x]  Wait for Douwe's review
        - [x]  Implement changes
        - [x]  Port changes to EE MR
        - [x]  Assign both back to Douwe
    - [ ]  Wait for merge
    - [ ]  Merge gitlab-org/gitlab-ee!718

See merge request !6215

Fix `User#to_reference`

## What does this MR do?

Fix the method signature of `User#to_reference` so that moving an issue with a user reference does not throw a "invalid number of arguments" exception.

## Why was this MR needed?

1. Changes in 8.13 require `Referable`s that don't have a project
   reference to accept two arguments - `from_project` and
   `target_project`.

2. `User#to_reference` was not changed to accept the
   `target_project` (even though it is not used). Moving an issue
   containing a user reference would throw a "invalid number of
   arguments" exception.

3. The regression was introduced in [c8b2b3f7](https://gitlab.com/gitlab-org/gitlab-ce/commit/c8b2b3f7c32db873f1bebce3e3b1847ea24d235f#91fabb7ad88bd2fde6fef1c100a719c00e503047_75_79), which expects
   all `Referable`s that don't respond to `:project` to have a `to_reference`
   method that takes two arguments.   

## Does this MR meet the acceptance criteria?

- Tests
  - [x] Added for this feature/bug
  - [ ] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [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 it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

- Closes #23662

See merge request !7088

Escape `ref` and `path` in `RelativeLinkFilter`.

fixes #21420

See merge request !6050

Add a note regarding syncing Git submodules in CI

Replaces https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7047

See merge request !7095

[ci skip]

Stop injecting field errors where they won't be used.

## What does this MR do?

Filters the form elements which gl_field_errors validates, excluding input types button, submit and checkbox.

## Why was this MR needed?

This won't make a difference in UX, but I just noticed that we are currently validating and injecting errors into the DOM for all non-hidden inputs. Doing so is unnecessary, and could introduce performance problems on forms with larger numbers of inputs.

## Does this MR meet the acceptance criteria?

- [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [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 it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !6929