Duplicating width and width in percents

This issue describes two things: feature request and fix of a bug, which I've found during implementing this feature. I would like to be able set width of inline maps not only in pixels, but in percents too. This looks better, works for most variety of screen sizes. And it works for openlayers in all browsers I've tried. Atached patch assumes, that if you supply number for width (previously you always had to supply number), width is pixels. If you specify other units, for example percents, they are used.
Now about a bug. I've found, that width and height were specified in resulting CSS twice. mapclient_common_open_map_block adds width and height to CSS even if it received style already contains them.