How to determine in which version an Android bug was fixed?
You already link the open source issue tracker. So I will assume you want a more in depth inquiry. Then just Go to Androids Gerrit code review and you can go directly here. Or you can go through Googles Git repository here then code review  in the upper right. Once there you can search for changes here is a tutorial. You can also review the code that will give you detailed information and here is a tutorial for that.