Unreviewed TestExpectations Update

Mark fast/dom/shadow/transition-on-shadow-host-with-distributed-node.html
as Pass Timeout on Linux as it times out intermittently.

BUG=318431
TBR=dglazkov@chromium.org

Review URL: https://codereview.chromium.org/60793003

git-svn-id: svn://svn.chromium.org/blink/trunk@161852 bbb929c8-8fbe-4397-9dbb-9b2b20218538