Powered by Gitiles (footer on https://go.googlesource.com ) and links to:

https://code.google.com/p/gitiles/

  Gitiles is a simple git repository browser built on JGit. 
  Emphasis on simple: the goal is to make it easy to see 
  your files and changes, leaving complex tasks to other 
  tools. 

  Gitiles is the source browser used by the Android Open 
  Source Project. To see it in action: 

https://android.googlesource.com/