rails/rails — pull request #6965 by davejachimiak (2012-07-04 17:22:38+00:00)
Title: Change 'Hash' to 'hash'.

test_rollback_when_saving_a_frozen_record in transactions_test.rb failed.
The runtime error's message returned 'hash' instead of 'Hash.' This commit
changes the test to reflect the message, which makes the test pass.