Signed-off-by: NRémy Coutable <remy@rymai.me>

- Fix naming of API::CommitStatuses
- Ensure we use require_dependency instead of require
- Ensure the namespace is right in lib/api/api.rb, otherwise, we
  might require Grape::API::Helpers which defines the `#params` method.
  This is to avoid requiring a file multiple times and getting an "Already
  initialized constant" error.
Signed-off-by: NRémy Coutable <remy@rymai.me>

Make all of the nested constant instrumentation for core app code work
the same way, add mailer instrumentation, and add instrumentation to the
premailer gem.

This reverts commit 1cc614f2.

It was causing the ActiveJob integration to fail, so unfortunately we'll have to add the gem again.

As described in their Docs: https://docs.getsentry.com/on-premise/clients/ruby/integrations/rails/

Without this setting your own trusted_proxies does not work.

Grack::Auth already checks this variable. These holdouts were not
disabled, leading to confusion when debugging a customer issue.

These changes were pulled from GitLab EE to support configuring
an alternative API URL than the default https://api.github.com.
In addition, the `verify_ssl` flag allows users to disable SSL cert
checking.

One modification: add a default `args` option if it does not exist
to avoid breaking existing configurations.

The extra gem isn’t necessary anymore since Rails 4.2 has ActiveJob integration.

Resolves #15575.

Daily seems to be to spammy, so let's default to weekly instead.

Adjust the default trusted_proxies to only include localhost, and allow other trusted proxies to be configured.

Closes #15105

Instrumenting this class together with Gitlab::ReferenceExtractor causes
a StackError for some reason. Since Gitlab::ReferenceExtractor has most
of the interesting code we'll only instrument that class.

Fixes gitlab-org/gitlab-ce#15162

This allows us to track how much time of a transaction is spent in
dealing with cached data.

Closes #14943.

I’ve removed everything related to the feature based on this commit:
ce08f919f34fd8849834365

Resolves #10857.

# Conflicts:
#	Gemfile.lock

This reverts commit 5a586f36

This reverts merge request !3191

Closes #13805

This code is mostly a copy-paste from existing pull requests so there's
no point in running Rubocop on it.

This ensures that options such as `using: :gin` and PostgreSQL operator
classes are ignored when loading a schema into a MySQL database.

This is needed to support creating/dumping/loading indexes that use the
gin_trgm_ops operator class on PostgreSQL. These changes are taken from
Rails pull request https://github.com/rails/rails/pull/19090.