Mark animations/combo-transform-translate+scale.html as flaky on Linux/Win Debug

BUG=327447
TBR=mkwst@chromium.org

Review URL: https://codereview.chromium.org/100103005

git-svn-id: svn://svn.chromium.org/blink/trunk@163570 bbb929c8-8fbe-4397-9dbb-9b2b20218538