Revert "Merge pull request #12778 from etehtsea/rake-default-fix"

This reverts commit 38cf00e553bc709cd1f9c4b14992d9730554f757.

Conflicts:
	railties/CHANGELOG.md
Upgrading Ruby on Rails guide is no longer WIP [ci skip]
Merge pull request #15482 from laurocaetano/fix-regression-for-eager-load

Fix regression on eager loading association based on SQL query rather than existing column.

Conflicts:
	activerecord/CHANGELOG.md
Do not try to set the foreign_key again on has_many through

Integration tests are inside protected_attributes test suite.

Fixes #15496
Fixes rails/protected_attributes#35
Timestamp values should be present on callbacks

This reverts commit dd3ea17191e316aeebddaa7b176f6cfeee7a6365 and add a
regression test.

Fixes #15418
Merge pull request #15701 from zzak/issue_15496

Open extension point for defining options in build_through_record
Preparing for 4.1.2.rc2 release
Auto-generate stable fixture UUIDs on PostgreSQL.
Fixes: #11524

Conflicts:
	activerecord/CHANGELOG.md
	activesupport/CHANGELOG.md