code: function nodeCollector_filterByDOMProperty(aProperty, aValue) {
      return this.filter(function(node) {
        if (aProperty && aValue)
          return node.getAttribute(aProperty) == aValue;
        else if (aProperty)
          return node.hasAttribute(aProperty);
        else
          return true;
      });
    }
docs: Filter nodes by DOM property and its value
  
  @param {string} aProperty
  Property to filter for
  @param {string} aValue
  Expected value of the DOM property
  [optional - default: n/a]
  
  @returns The class instance
  @type {object}