* Allow overshooting maximum when there are no bandwidth constraints.
Some clients prioritize sending higher layer of video (for e.g.
Firefox). They may get into a state where congestion does not allow
sending lower layers.
That combined with adaptive streaming capping the max layer at a
certain level, it is possible to get into a state where video is
not streamed.
To make this experience better, allow overshoot beyond max layers
in case of optimal (i. e. no congestion) allocation.
NOTE: This means that the video could freeze when there is congestion
even if `AllowPause` is not disabled as in congested state, we do
not overshoot the max layer.
* log about allowing overshoot