I have run into this a few times and it always bothers me. Google has an auto fill function for forms that is sometimes really handy as a user, but sometimes breaks ui elements if you are a dev.
This is especially bad with the Google Address search because it seems to reset your autofill / autocomplete attributes each time you focus on the element.
If you are running into this issue here is a good thread with a couple good solutions for hiding the autofill.
The jQuery solution is what I found worked best for myself.