title: ionic mouse scroll not working when using $scope.overflow_scroll='true'; in controller
body: <p>Directly set overflow-scroll="true" in html is no problem for mouse scroll on desktop browser.</p>
  
  <pre><code>&lt;ion-content padding="true" overflow-scroll="true"&gt;
  </code></pre>
  
  <p>But use $scope.overflow_scroll='true'; in controller, and overflow-scroll="{{overflow_scroll}}" in html, the mouse scroll will not work on desktop browser.</p>
  
  <pre><code>.controller('HomeTabCtrl', function($scope) {
   $scope.overflow_scroll='true';
  });
  </code></pre>
  
  <p>and</p>
  
  <pre><code>&lt;ion-content padding="true" overflow-scroll="{{overflow_scroll}}"&gt;
  </code></pre>
  
  <p><a href="http://codepen.io/anon/pen/pjJvXo" rel="nofollow">Here is the live demo</a></p>
  
  <p>Any help would be much appreciated. Best Regards.</p>