How tab goes animate in Chrome When twitter have a new tweet. any idea to do this for own website?

I a开发者_如何转开发dd twitter.com as pin tab in chrome. now it's always open in left side of my chrome. now in Chrome beta i found a new little thing that when new tweets come to my account and i am on others tab i can see a animation on chrome. they look like something like Rain season.

can someone tell me what else i can do as they done. what's it's called. are someone can show me the code for do this thing in javascript.