Well I don't have the 4.4 source and neither do I have a computer.....mine is broken. Bought one on amazon but I'll take three weeks to get here . @jolinnard already pointed out that rotation control can be found in phonewindowmanager.java in frameworks base. But instead of looking at the full source maybe we can look in android policy.jar. There are multiple files in there named phonewindowmanager, maybe one handles rotation? Also if you use Virtuous Ten Studio you can generate a phonewindowmanager.java file from androidpolicy.jar. I don't know if its the same as can be found in frameworks base of the rom source though.
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer?