activerecord tests should inherit from ActiveRecord::TestCase

activerecord/test/cases/adapters/postgresql/active_schema_test.rb

@@ -1,6 +1,6 @@
 require 'cases/helper'
 
-class PostgresqlActiveSchemaTest < Test::Unit::TestCase
+class PostgresqlActiveSchemaTest < ActiveRecord::TestCase
   def setup
     ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.class_eval do
       alias_method :real_execute, :execute

activerecord/test/cases/i18n_test.rb

@@ -2,7 +2,7 @@
 require 'models/topic'
 require 'models/reply'
 
-class ActiveRecordI18nTests < Test::Unit::TestCase
+class ActiveRecordI18nTests < ActiveRecord::TestCase
 
   def setup
     I18n.backend = I18n::Backend::Simple.new

activerecord/test/cases/invalid_date_test.rb

@@ -1,7 +1,7 @@
 require 'cases/helper'
 require 'models/topic'
 
-class InvalidDateTest < Test::Unit::TestCase
+class InvalidDateTest < ActiveRecord::TestCase
   def test_assign_valid_dates
     valid_dates = [[2007, 11, 30], [1993, 2, 28], [2008, 2, 29]]
 

activerecord/test/cases/log_subscriber_test.rb

@@ -2,7 +2,7 @@
 require "models/developer"
 require "active_support/log_subscriber/test_helper"
 
-class LogSubscriberTest < ActiveSupport::TestCase
+class LogSubscriberTest < ActiveRecord::TestCase
   include ActiveSupport::LogSubscriber::TestHelper
 
   def setup