Fix box-shadow parsing for IE9

In IE window.getComputedStyle().boxShadow value has different order of color, dimensions and inset parts than in chrome/firefox. Also dimensions count can be less than 4 (as was specified in in the source css). So regexp is changed a little and shadow string is splat by a comma. Every splat part is matched against regexp to extract dimensions. Inset is checked by just using indexOf() on every splat part.
Не подходит. Цифры могут быть не только те что нам нужны.