Make LeftNavEditTutorial no longer an A/B test

We now display the LeftNavEditTutorial to all new users who sign-up
from the left nav sidebar.

Also removing eventTracking code that is no longer needed.

Change-Id: I7a861dfd9854a069d662386c6173a3c82268168f
Merge "Make LeftNavEditTutorial no longer an A/B test"