I'll take it.
On my machine the test fails 4/5 times due to image differences. The tests goal is to immediately seek to the end of a media file. Sometimes the seek is issued quickly enough for most of the file to have not downloaded (doing only a range request for the last few milliseconds). When this occurs the seek bar is shown as mostly grayed out (rather than solid blue) because the bulk of the file is not buffered.
I explored this in https://codereview.chromium.org/2439083003/
In that CL, I hit a wall because I tried to convert to using testharness.js only to realize it doesn't support pixel diff tests. Then it fell off my radar.
If you're interested, feel free to take it. Otherwise it will probably get very slow p3 treatment from me - pretty overloaded atm.
Comment 1 by guidou@chromium.org
, Aug 17 2016