Netflix/RxJava — pull request #863 by Acardiac (2014-02-12 12:53:06+00:00)
Title: Optimize SwingMouseEventSource.fromRelativeMouseMotion

do it more functional way
see the trick here:
http://www.introtorx.com/Content/v1.0.10621.0/12_CombiningSequences.html#Zip