premailer/css_parser — pull request #53 by rafeca (2014-07-22 20:55:09+00:00)
Title: Do not short single properties

This PR prevents css_parser to convert single declarations to their respective shorthand.

So, if there is a single declaration in a selector like `background-color: #fff;`, it won't be converted to `background: #fff` and thus it won't overwrite declarations like `background-image` on other css rules.