This worked for me without root some time ago but it might still work.
Once you set up your account install this apk
Put in your account info and then hit the free 50g tab below it.
Then I checked and my 50g were there on my account. After that I
Changed the password on my account just to be safe.
I did this via my xoom fe by the way.
Good luck and let use know if this still works.
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