Mark several layout tests as flaky.

- css3/filters/effect-brightness-clamping-hw.html
- virtual/gpu/fast/canvas/canvas-blending-image-over-image.html
- css3/filters/effect-drop-shadow-hw.html
- external/wpt/html/syntax/parsing/template/creating-an-element-for-the-token/template-owner-document.html

TBR=kpaulhamus@chromium.org

Bug: 862716, 862729, 862806, 862826
Change-Id: I08126b22afdc0a7a4ef776dde8cc1120643acdcc
Reviewed-on: https://chromium-review.googlesource.com/1134990
Commit-Queue: Mike West <mkwst@chromium.org>
Reviewed-by: Mike West <mkwst@chromium.org>
Cr-Commit-Position: refs/heads/master@{#574539}
1 file changed