title: Angular bind string date to input type date
body: <p>I am using Angular 1.6 and I would like to directly bind a string to an input of type date instead of having to convert the date to a Date and then bind to the input. The reason is that I get JSON (along with other data) from the server and I don't want to create an intermediary variable only for the date, I want to use directly the JSON, and thus I can POST back my JSON as is when there are modifications in input field and no need to use ng-change and convert date and put it my JSON, etc... I have <a href="http://plnkr.co/edit/hBBfE3N0Xk8yu7xaCRht?p=preview" rel="nofollow noreferrer">plunkered</a> my issue. </p>
  
  <p>Here is the html :</p>
  
  <pre><code>&lt;body ng-app="plunker" ng-controller="MainCtrl"&gt;
    &lt;form name="myForm"&gt;
      &lt;label for="exampleInput"&gt;Date input&lt;/label&gt;
      &lt;input type="date" id="exampleInput" name="input" ng-model="date" placeholder="yyyy-MM-dd"/&gt;
    &lt;/form&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p>And here is the javascript :</p>
  
  <pre><code>var app = angular.module('plunker', []);
  app.controller('MainCtrl', function($scope) {
    $scope.dateString = '2017-01-31';
    $scope.date = new Date(2017, 11, 31);
  });
  </code></pre>
  
  <p>If I bind the input to variable $scope.date it is OK but it is KO if I bind it to variable $scope.dateString.</p>