The css3/viewport-percentage-lengths/vh-resize.html layout test is flaky on GTK. It has an image failure sometimes. The diff is the following: https://build.webkit.org/results/GTK%20Linux%2064-bit%20Release%20%28Tests%29/r182941%20%287770%29/css3/viewport-percentage-lengths/vh-resize-diffs.html
The test(s) filed under this bug have been consistently passing for the last 4000 revisions. Marking bug as fixed. Committed r263254: <https://trac.webkit.org/changeset/263254>
<rdar://problem/64522495>
<rdar://problem/64522497>