angular/angular.js — pull request #2643 by danielstockton (2013-05-11 21:33:19+00:00)
Title: Give PATCH requests the same default headers as PUT and POST

Is there any reason why PATCH requests shouldn't be sent with a content-type of application/json as well as PUT and POST?

It caused me some problems I wasn't expecting when working with a rails 4 application (PATCH is the new preferred verb for update operations).