The fast/events/touch/touch-coords-in-zoom-and-scroll.html layout test is flaky on GTK+. It fails sometimes. When it fails the diff is the following: https://build.webkit.org/results/GTK%20Linux%2064-bit%20Release%20%28Tests%29/r184378%20%288602%29/fast/events/touch/touch-coords-in-zoom-and-scroll-pretty-diff.html