This reverts commit c99d507f.

Stub ip method of alternative request class in router tests

Use Rack::BodyProxy

it's needed until new rack release with Rack::BodyProxy fixes
https://github.com/rack/rack/commit/b06ef82876416fe69429f7d3ee6e51bf26aec75f

show stats for app/mailers

TL;DR: MySQL sucks.

Since it does not support transactions for schema changes,
when you run `create_table` in setup block, it will commit
current transaction. Now tests want to run `RELEASE SAVEPOINT`
after finishing tests which fails since there is no transaction.

* Calified how assets are included.
* Added information about using index manifests.

#4472

SchemaMigration model is loaded on rails initialization,
which means that it will not be cleaned on each request.

Without that patch when using ActiveModel::AttributeMethods
in a class that does not respond to `attributes` method,
stack level too deep error will be raised on non existing
method. While documentation is clear that you need to define
`attributes` method in order to use AttributeMethods module,
`stack level too deep` is rather obscure and hard to debug,
therefore we should try to not break `method_missing` if
someone forgets about defining `attributes`.

The commit 2f632f53 extracted the
options into constants and while doing so, there was a minor error of
using a wrong constant name.

changelog entry for deprecated ActionController::Integration, ActionCont...

Don't hardcode assets route skipped in route inspector

Bump Sprockets to 2.2.0 in master

Refactored watchable_args and build_original_fullpath methods in Rails::Application

Generated attributes refactor

changelog entry for deprecated ActionController::Integration, ActionController::IntegrationTest, ActionController::PerformanceTest,ActionController::AbstractRequest, ActionController::Request, ActionController::AbstractResponse others