googleads/google-media-framework-android — pull request #7 by hariharsubramanyam (2014-07-24 22:10:52+00:00)
Title: Fixed bug where video does not resume after putting app into background ...

Fixed bug where video does not resume after putting app into background and returning to app.

The issue was that the track states were stored in an enum, instead of as constant ints (-1 for disabled and 0 for primary). Apparently, those two values are important in ExoPlayer, so using an enum instead of ints caused problems.