* Use String#sub with RegEx instead of String#delete_prefix

* Use match instead match?
* Use String#chomp instead of String#delete_prefix

* Use match instead match?

This reverts commit ca3e9b97, reversing
changes made to 89686b90.

The way Discord integration is implemented causes dependency problems.

This reverts commit 07ec2c7b.

* Use match instead match?

This was renamed in GitLab 11.11, so the backport needs to use
the original name.

First reported:
  https://gitlab.com/gitlab-org/gitlab-ce/issues/60143

When the page slug is "javascript:" and we attempt to link to a relative
path (using `.` or `..`) the code will concatenate the slug and the uri.
This MR adds a guard to that concat step that will return `nil` if the
incoming slug matches against any of the "unsafe" slug regexes;
currently this is only for the slug "javascript:" but can be extended if
needed. Manually tested against a non-exhaustive list from OWASP of
common javascript XSS exploits that have to to with mangling the
"javascript:" method, and all are caught by this change or by existing
code that ingests the user-specified slug.

Gitlab::HTTP now resolves the hostname only once, verifies the IP is not
blocked, and then uses the same IP to perform the actual request, while
passing the original hostname in the `Host` header and SSL SNI field.

Fix milestone titles being leaked using search API
when users cannot read milestones

Prevents refspec as branch name, which would bypass branch protection
when used in conjunction with rebase.

HEAD seems to be a special case with lots of occurrence,
so it is considered valid for now.

Another special case is `refs/head/*`, which can be imported.

Refactor api events class to use external helper

Move specs from old class

Add changelog and magic string

Refactor events class to be more explicit

Remove blank line

Bring back Rugged implementation of ListCommitsByOid

See merge request gitlab-org/gitlab-ce!27441

(cherry picked from commit 6a72ab22c824c17e311492888fc99473a5c89192)

2fc4de6a Bring back Rugged implementation of ListCommitsByOid

This reverts commit 348d5a1d, reversing
changes made to 93e32156.

[11.9] Revert "Remove HipChat integration from GitLab"

See merge request gitlab-org/gitlab-ce!27257

This reverts commit a5378665.

Improve performance of PR import

See merge request gitlab-org/gitlab-ce!27121

(cherry picked from commit f15caf0109998308e7f960baaa541d73be8bcacb)

f3ad51f8 Improve performance of PR import

Allow to use untrusted ruby syntax

See merge request gitlab-org/gitlab-ce!26905

(cherry picked from commit 7dcc3003)

9bc4fbf1 Allow to use untrusted Regexp via feature flag

Fix attempting to drop views in PostgreSQL

See merge request gitlab-org/gitlab-ce!26836

(cherry picked from commit 264a6299)

cfc6d252 Fix attempting to drop views in PostgreSQL

Avoid excessive recursive calls with Rugged TreeEntries

Closes #59759

See merge request gitlab-org/gitlab-ce!26813

(cherry picked from commit d7583add)

8686e012 Avoid excessive recursive calls with Rugged TreeEntries

Fix API /project/:id/branches not returning correct merge status

Closes #56250

See merge request gitlab-org/gitlab-ce!26785

(cherry picked from commit 2db4e79f)

cedbb336 Fix API /project/:id/branches not returning correct merge status
2675581c Revise merged branch check to green light up to N branches

Force to recreate all diffs on import

Closes #59353

See merge request gitlab-org/gitlab-ce!26480

(cherry picked from commit afb6e8e3)

7fbfb199 Force to recreate all diffs on import

Adds a rake task which can be used for removing EXIF
data from existing uploads.

GitHub importer: Use the project creator to create branches from forks

Closes #59396

See merge request gitlab-org/gitlab-ce!26510

Set proper default-branch on GitHub Import

Closes #59347

See merge request gitlab-org/gitlab-ce!26476

(cherry picked from commit 3eba3a18)

31fb85d5 Set proper default-branch on GitHub Import

Allow users to create protected branches via CLI

Closes #59289

See merge request gitlab-org/gitlab-ce!26413

(cherry picked from commit b36fc6d5)

438485ef Allow users to create protected branches via CLI

Fix duplicated bottom match line

Closes #59147

See merge request gitlab-org/gitlab-ce!26402

(cherry picked from commit 7d3c5d88)

8723f292 Fix diff bottom expand button appears twice

Merge branch '59208-fix-error-500-on-every-page-when-active-broadcast-message-present-after-upgrading-to-11-9-0' into 'master'

Gracefully handles excluded fields from attributes during serialization on JsonCache

Closes #59208

See merge request gitlab-org/gitlab-ce!26368

(cherry picked from commit cc5095ed)

7028b376 Gracefully handles excluded fields from attributes during serialization
1c7a2c05 Add CHANGELOG entry

GitHub import: Create new branches as project owner

See merge request gitlab-org/gitlab-ce!26335

(cherry picked from commit 6e74eb4e)

1e6ea914 GitHub import: Create new branches as project owner