SQLite3Adapter now checks for views in table_exists? fixes: 14041
disable migrations logging while running test cases for AR schema tests
Add support for Rack::ContentLength middelware
Fix query with nested array in Active Record

`User.where(id: [[1,2],3])` was equal to `User.where(id:[1, 2, 3])`
in Rails 4.1.x but because of some refactoring in Arel this stopped
working in 4.2.0. This fixes it in Rails.

[Dan Olson & Cristian Bica]
Merge pull request #16793 from javan/comply_with_rack_content_length_middleware

Add support for Rack::ContentLength middelware
Ignore segfault build errors with 2.0.0 + mysql-ruby

Continuation of c9a43126c5e2c608ab3ff1be994bce69e815a144

:cry:
[guides] Use `match ..., via: :all` in the custom exceptions app [ci skip]

Using `get` results in an unexpected error page(returning empty body) for requests of other HTTP mehtods other than GET. Use `match ..., via:
:all` so the exceptions app can be more stable.
Merge pull request #16832 from yuki24/use-match-via-all-in-custom-exceptions-app

[guides] Use `match ..., via: :all` in the custom exceptions app [ci skip]
Convert string concatenations to substitutions
Prefer "if any?" to "unless empty?"

* Consistent whitespace
* Remove unnecessary parentheses
Fix warnings for undefined local variable

* Add private method primary_key_for, which more clearly shows that the
expected return value is nil when a primary key is not found.
Merge pull request #16830 from teeparham/schema_dumper

Cleanup SchemaDumper
Schema dumper: all connection adapters implement #primary_key, so rely on it exclusively
Removing unused fake models
Merge pull request #16834 from tchandy/removing_unused_fake_models

Removing unused fake models
Merge pull request #16825 from cristianbica/fix-ar-nested-arrays

Fix query with nested array in Active Record
Merge pull request #16827 from kuldeepaggarwal/f-disable-migration-logging

disable migrations logging while running test cases for AR schema tests
Do not memoize document_root_element in view tests

Memoizing will not make possible to assert the output of the view if it
is changed after the first assert_select call

Related with plataformatec/simple_form#1130 and rails/rails-dom-testing#15
Add docs for web-console to 4.2 Upgrade Guide [ci skip]
Merge pull request #16845 from todd/upgrade_guide_console_docs

Add docs for web-console to 4.2 Upgrade Guide