code: function checkIfNodeCanBeChildOfStyle( def, currentNode, lastNode, nodeName, dtd, nodeIsNoStyle, nodeIsReadonly, includeReadonly ) {
  		// Style can be applied to text node.
  		if ( !nodeName )
  			return 1;
  
  		// Style definitely cannot be applied if DTD or data-nostyle do not allow.
  		if ( !dtd[ nodeName ] || nodeIsNoStyle  )
  			return 0;
  
  		// Non-editable element cannot be styled is we shouldn't include readonly elements.
  		if ( nodeIsReadonly && !includeReadonly  )
  			return 0;
  
  		// Check that we haven't passed lastNode yet and that style's childRule allows this style on current element.
  		return checkPositionAndRule( currentNode, lastNode, def, posPrecedingIdenticalContained );
  	}
docs: Checks if the current node can be a child of the style element.