title: ng-click doesn't work with md-button
body: <p>My html and javascript are as follows, I have the following element </p>
  
  <pre><code>&lt;i class="material-icons" ng-click="clicked()" md-48&gt;add_circle&lt;/i&gt;
  </code></pre>
  
  <p>Which works when clicked i.e. by bringing up a dialog, however the following on the same page does not work.</p>
  
  <p>html</p>
  
  <pre><code>&lt;body ng-cloak&gt;
    &lt;div ng-cloak ng-controller="mainController" &gt;
      &lt;div layout="row" layout-align="end end"&gt;
        &lt;md-button aria-label="Eat cake" ng-click="clicked()"&gt;&lt;/md-button&gt;
       &lt;/div&gt;
     &lt;/div&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p>angular</p>
  
  <pre><code>angular.module('notifyMe', ['ngMaterial', 'material.svgAssetsCache'])
  
      .controller('mainController', function($scope, $mdDialog) {
      $scope.clicked = function () {
          alert('Worked!');
      };
      })
  </code></pre>