Add pref layout.css.supports-rule.enabled from http://hg.mozilla.org/mozilla-central/rev/1c8ab97bf848
Add pref layout.css.supports-rule.enabled from http://hg.mozilla.org/mozilla-central/rev/1c8ab97bf848

nth10sd/funfuzz,MozillaSecurity/funfuzz,nth10sd/funfuzz,MozillaSecurity/funfuzz,MozillaSecurity/funfuzz,nth10sd/funfuzz