o2Labs/handshake-html5-vibrate-haptic-library — pull request #15 by TalAter (2014-01-25 01:42:00+00:00)
Title: Does not overwrite the native vibrate object

No longer overrides the browser's own navigator.vibrate, but instead places the object you've found (or undefined) into a variable.
In addition, I would suggest handling cases where no implementation of vibrate is found (ie vibrator is undefined) #14