CheckVarFunction parse a var(...) token.

ExpandFont expands the 'font' property.

Expand shorthand properties and filter unsupported properties and values.

Remove any top-level whitespace in a token list.

Split a list of tokens on commas, ie “parser.LiteralToken(",")“.

Validate validate one property.

http://drafts.csswg.org/csswg/css3-values/#angles 1<unit> is this many radians.

http://drafts.csswg.org/csswg/css-values/#resolution.