2) Create a new repository into the root folder, in my case (win 7) will be C:\Users\<user>\AppData\Local\Google\Chrome\User Data

- Notice that the root is not your account, but the folder above of your account

- In this way you sync all the users and other important/global stuff

3) Your .gitignore file should look like this:

  */Application Cache/*
  */Cache/*
  */Media Cache/*

 - In order to don't fill your git repository with cache data!

5) Have fun and never ever lose your synced data!!!

Why?

- google chrome delete sync data (13 200 000 results)

- http://productforums.google.com/forum/#!topic/chrome/45bCWXEh-vQ