Remove ActionController::RaiseActionExceptions.

The latest modification to the code was done in https://github.com/rails/rails/commit/5e3517ea. In Rails 3.2,
`ActionController#rescue_action` was deprecated and `rescue_action_without_handler` is no longer being used.
Merge pull request #16419 from tgxworld/remove_legacy_code

Remove ActionController::RaiseActionExceptions.