Sabberworm\CSS\RuleSet\DeclarationBlock::createFontShorthand
Looks for long format CSS font properties (e.g. <tt>font-weight</tt>) and tries to convert them into a shorthand CSS <tt>font</tt> property.
At least font-size AND font-family must be present in order to create a shorthand declaration.
Signature
public function createFontShorthand()