whole_func_string: function isValidIdentifier(it) {
  //		return true;
  		var tokens = it.tokens;
  		for (var i = it._i + 1, il = tokens.length; i < il; i++) {
  			if (tokens[i].type == ':')
  				return true;
  			
  			if (tokens[i].type == 'identifier' || tokens[i].type == 'line')
  				return false;
  		}
  		
  		return false;
  	}
func_code_string: function isValidIdentifier(it) {
  //		return true;
  		var tokens = it.tokens;
  		for (var i = it._i + 1, il = tokens.length; i < il; i++) {
  			if (tokens[i].type == ':')
  				return true;
  			
  			if (tokens[i].type == 'identifier' || tokens[i].type == 'line')
  				return false;
  		}
  		
  		return false;
  	}
func_documentation_string: A bit hacky way to identify invalid CSS property definition: when user
  starts writing new abbreviation in CSS rule, he actually creates invalid
  CSS property definition and this method tries to identify such abbreviation
  and prevent it from being added to CSS edit tree
  @param {TokenIterator} it