

<link rel="import" href="../utils/boot.html">
<link rel="import" href="../utils/mixin.html">
<link rel="import" href="../utils/case-map.html">
<link rel="import" href="../utils/async.html">

<script>
(function() {

  'use strict';

  let caseMap = Polymer.CaseMap;

  let microtask = Polymer.Async.microTask;

  // Save map of native properties; this forms a blacklist or properties
  // that won't have their values "saved" by `saveAccessorValue`, since
  // reading from an HTMLElement accessor from the cont