media/controls-styling.html has non-filled scrubber background on one of the videos. Jer and myself noticed the problem on Yosemite, but that's only because text results fail there. It seems likely that the actual failure is cross-platform, and we just don't detect it.
This test was removed in this commit: https://github.com/WebKit/WebKit/commit/a39bd42ad87d82a3bea0fa6eac107376a973cf7c Nothing much to do here. Marking this as "RESOLVED CONFIGURATION CHANGED".