729b6da76a
This reverts commit 7335ce5d3e03c126a417a721571cb6f3af136ecf. Support abusing the uri property to configure the next uri to play outside of the about-to-finish handler for the time being after all. We also shouldn't use thread private structures for this, since it should be possible to block the thread that emitted about-to-finish while the main thread sets the uri property. See #607226.