each to each_value; remove unused vars

Added a bang to the raise_nested_attributes_record_not_found method

method to signify an exception possibly being raised.

Refactoring some reused code into a method (inside of the routes mapper)

Related with 57583879

Fix markdown formatting

change some more merge to merge! on new hashes

See https://travis-ci.org/rails/rails/jobs/6110543#L1285 for the failure

cc @josh

Deprecate ActiveRecord#Base.default_scopes?

Closes #10107

See #10107.

remove unused variables

Remove extra whitespace

Also, print out deprecation warning for other rake tasks except
`rake test` and `rake` (default)

Conflicts:
	railties/lib/rails/test_unit/testing.rake
	railties/test/application/rake_test.rb

* railstest:
  do not blow away the test database on every run
  just check pending migrations in the current environment
  check pending migrations against the test db
  only match the default task
  test no longer makes sense after requiring all test files
  switch the testing tests to use rake
  a test file can be provided to rake, e.g.:
  switch to Rails::TestTask
  default task should also be in the test env
  ensure the schema checking is done in the dev connection
  Revert "Update Rake tasks to call `rails test` instead"
  Revert "Warning removed unused variable task_name"
  apps that depend on active record should load fixtures

* master: (44 commits)
  Improve the changelog entry [ci skip]
  Fix explicit names on multiple file fields
  Correctly parse bigint defaults in PostgreSQL
  Move changelog to the top [ci skip]
  Fix indent and remove extra white spaces
  Fix scope chaining + STI
  failing test for #9869
  Improve `belongs_to touch: true` timestamp test
  Sort modules in alphabetical order.
  Avoid an attempt to fetch old record when id was not present in touch callback
  Use the correct pk field from the reflected class to find the old record
  Refactor mail_to to not generate intermediate hashes when adding href
  Ensure mail_to helper does not modify the given html options hash
  Use inspect when writing the foreign key from the reflection
  Use a space after the comment sign when showing the result of commands
  Exclude template files for rdoc API [ci skip]
  template should have generic name
  use | to have more intent revealing code
  Revert "Merge pull request #10034 from benofsky/fix_skipping_object_callback_filters"
  stop depending on callbacks
  ...

Conflicts:
	railties/test/application/rake_test.rb

Removed space and unused class

Removed unnecessary class

Optimize generated ERB to reduce method calls

Fix explicit names on multiple file fields

If a file field tag is passed the multiple option, it is turned into an
array field (appending "[]"), but if the file field is passed an
explicit name as an option, leave the name alone (do not append "[]").

Fixes #9830