Using Espresso on Error message during editing preferences

[raacker]

I was working on HelloActivity

and I found that using espresso would be really great with this! http://blog.xebia.com/android-custom-matchers-in-espresso/

How about it?

[emartynov]

Go for it! More quality tests is better!

[ArunSelvam11]

i have given a pull request for this issue, please review it. https://github.com/Glucosio/glucosio-android/pull/402