code: function makeArrayObservable(arr, observer, proxyArrApis) {
      // Here, not using __proto__ implementation, there are two import reasons:
      // First, considering __proto__ will be deprecated and is not recommended to use
      // Second, some plugins like weixin contact plugin will change array definition,
      // the array instance __proto__ property does not contains any like `push`
      // `pop` API, and these API only existed in the instance context.
      // So, like the code as the following will not work correctly,
      // a = []; // a.__proto__.push is not defined, a.push is defined
      // a.__proto__.push = function () {};
      // a.push(2); // always call the native push, not the override push method
      // Therefor, using __proto__ to proxy the array method will not work
  
      Object.keys(proxyArrApis).forEach(method => {
          let rawMethod = arr[method];
          arr[method] = proxyArrApis[method].bind(arr, observer, rawMethod);
      });
  
      arr.setItem = updateArrayItem.bind(arr, observer);
      arr.getItem = getArrayItem.bind(arr, observer);
  
      return arr;
  }
docs: Make array observable
  
  @param {Array} arr the array to observe
  @param {Observer} observer the observer
  @param {Object} proxyArrApis the array api to proxy
  @return {Array}