yui/yui3 — pull request #1576 by adinardi (2014-01-23 23:07:57+00:00)
Title: Fix Amazon Silk detection in Y.UA.

The UA string for Amazon Silk on recent Kindle Fires changed causing Y.UA.silk to no longer be set.

Amazon updated the UA string as specified here:
http://docs.aws.amazon.com/silk/latest/developerguide/user-agent.html