Mark fast/dom/shadow/input-color-in-content.html as crashing on Mac dbg

BUG=362073
TBR=leviw@chromium.org

Review URL: https://codereview.chromium.org/233183003

git-svn-id: svn://svn.chromium.org/blink/trunk@171273 bbb929c8-8fbe-4397-9dbb-9b2b20218538