title: Android Room DB: Cannot run invalidation tracker. Is the db closed?
body: <p>I'm using ROOM DB for Android.
  I have a same issue with <a href="https://stackoverflow.com/questions/50420649/upgrading-room-db-with-migrations-causes-db-lock">Upgrading Room DB with migrations causes DB lock</a></p>
  
  <p>My ROOM version is 1.1.1-rc and the problem occurs again.
  I think there are temporary solutions such as changing DB name, etc. However, it is not the exact solution for migration.</p>
  
  <p>Is there any solution for this problem?
  Thanks. </p>