Missing repair_validations
Reset table_name_{prefix,suffix}, and table_name after each test

because some tests were not resetting them, and thus the tests were order dependent
Ignore "SHOW search_path" when counting PostgreSQL queries
Be sure to clear schema cache
Ignore schema queries on SQLite 3 as well
Preload some join table schemas
Make sure to reset default_url_options
Restore I18n.locale after running tests
Reset SchemaMigration after updating
Just ignore all PRAGMA queries
Merge branch 'isolating_tests'

Now we're almost ready to remove this: https://github.com/rails/rails/blob/5294ad8/activesupport/lib/active_support/test_case.rb#L29