ZF-8056: View Helper HeadStyle does not accept comma separated strings with spaces for media attribute
When using headStyle, the media attribute works when set to 'screen,projection' or array('screen', 'projection') but not 'screen, projection' (with a space).
This is inconsistent with headLink which accepts the space, and the css specifications which allow the space: http://www.w3.org/TR/CSS2/media.html
This is because, unlike headLink, headStyle for some reason checks the media types specified, and retrieves them from the string using explode (which will leave extra spaces). This also means that headLink and headStyle treat the media attribute differently in another way (headLink allows any media type, headStyle only allows those specified in its code).