Bug 1025711 - [email/sanitizer] Quiet bleach.js CSS parser errors. r=jrburke

land https://github.com/mozilla-b2g/bleach.js/pull/8
Merge pull request #314 from asutherland/quiet-css-errors

Bug 1025711 - [email/sanitizer] Quiet bleach.js CSS parser errors. r=jrburke