Encompasses designs from
 - https://gitlab.com/gitlab-org/gitlab-ce/issues/23206#note_43355199
 - https://gitlab.com/gitlab-org/gitlab-ce/issues/29985#note_30417407

Refactored multi-file data structure

See merge request gitlab-org/gitlab-ce!14862

Add inline edit button to issue_show app

See merge request gitlab-org/gitlab-ce!14875

Change project deletion message from alert to notice

Closes #26956

See merge request gitlab-org/gitlab-ce!14756

Merge branch '20930-very-first-commit-to-default-branch-didn-t-close-referenced-issue' into 'master'

Fix #20930: automatic closing is not triggered on very first push.

Closes #20930

See merge request gitlab-org/gitlab-ce!11899

Move user avatar specs to folder to mimic javascript directory

Closes #39169

See merge request gitlab-org/gitlab-ce!14901

Improve sprite icon spec

Closes #39199

See merge request gitlab-org/gitlab-ce!14914

Avoid using `Redis#keys`

See merge request gitlab-org/gitlab-ce!14889

Fix errors when deleting a forked project

Closes #39196

See merge request gitlab-org/gitlab-ce!14916

Use variable for mobile breadcrumbs padding

Closes #38156

See merge request gitlab-org/gitlab-ce!14904

The problem would occur when the `ForkedProjectLink` was deleted, but
the `ForkNetworkMember` was not. The delete would be rolled back and
retried.

But the error would not be saved because `Project#forked?`
would still be true, because the `ForkNetworkMember` exists. But the
`Project#forked_project_link` would be `nil`. So the validation for
the visibility level would fail.

Prevent creating multiple ApplicationSetting by forcing it to always have id=1

Closes #34728

See merge request gitlab-org/gitlab-ce!14718

Merge branch '39181-gitlab-backgroundmigration-deserializemergerequestdiffsandcommits-error-nomethoderror-undefined-method-map-for-nil-nilclass' into 'master'

Resolve "Gitlab::BackgroundMigration::DeserializeMergeRequestDiffsAndCommits::Error: #<NoMethodError: undefined method `map' for nil:NilClass"

Closes #39181

See merge request gitlab-org/gitlab-ce!14907

Adds collapsible sections in cluster page

See merge request gitlab-org/gitlab-ce!14890

This is already handled for diffs, but not commits.

Allow testing on Gitaly call count

See merge request gitlab-org/gitlab-ce!14837

Clarify how to resume GitHub import on docs

See merge request gitlab-org/gitlab-ce!14905

Bump Git version to 2.13.6

See merge request gitlab-org/gitlab-ce!14906

Make the circuitbreaker configurable at runtime

See merge request gitlab-org/gitlab-ce!14842

Adds a test for flattenedFiles
Changes the data method to not be an arrow method
Various other review fixes

Show collapsible tree on the project show page

Closes #30343

See merge request gitlab-org/gitlab-ce!14055

Instead of from the configuration file

Add ability to pass class name to spriteIcon helper

Closes #39079

See merge request gitlab-org/gitlab-ce!14855

Fix link to "Job Permissions"

See merge request gitlab-org/gitlab-ce!14896

Remove extra border radius when editing a file

Closes #37978

See merge request gitlab-org/gitlab-ce!14803