Web Hooks don't work in GitLab 2.4.1

Created by: joschi

Since upgrading from GitLab 2.2.0 to 2.4.1 the web hooks feature doesn't work any more.

When clicking on "Test Hook" ("Project" -> "Hooks" -> $hook -> "Test Hook") the application generates an internal server error.

The logs contain the following error messages:

Started GET "/my_project/hooks/8/test" for 178.26.45.75 at 2012-04-26 12:14:15 +0200
Processing by HooksController#test as HTML
  Parameters: {"project_id"=>"my_project", "id"=>"8"}
Completed 500 Internal Server Error in 80ms

NoMethodError (undefined method `web_hook_data' for #<Project:0x00000005ca55f8>):
  app/controllers/hooks_controller.rb:35:in `test'

A quick git grep and a look into app/models/project.rb reveals that there is no method definition for web_hook_data in the whole project.