Gardening: fast/events/touch/gesture/pad-gesture-fling.html is still flaky on Windows 7 Release.

BUG=261277
TBR=bokan@chromium.org

Review URL: https://codereview.chromium.org/24064003

git-svn-id: svn://svn.chromium.org/blink/trunk@157432 bbb929c8-8fbe-4397-9dbb-9b2b20218538