title: Scroll not working with md-select in angular js
body: <p>This is my view code......</p>
  
  <pre><code>&lt;md-select aria-label="..." ng-model="topping"&gt;
                  &lt;md-option&gt;Show All&lt;/md-option&gt;
                  &lt;md-option&gt;Fit width&lt;/md-option&gt;
                  &lt;md-option&gt;Full Size&lt;/md-option&gt;
                  &lt;div style="height: 100px;overflow-y: scroll; border-top: 1px solid #ccc"&gt;
                      &lt;md-option&gt;100%&lt;/md-option&gt;
                      &lt;md-option&gt;75%&lt;/md-option&gt;
                      &lt;md-option&gt;50%&lt;/md-option&gt;
                      &lt;md-option&gt;33.33%&lt;/md-option&gt;
                      &lt;md-option&gt;25%&lt;/md-option&gt;
                      &lt;md-option&gt;12.5%&lt;/md-option&gt;
                      &lt;md-option&gt;8.33%&lt;/md-option&gt;
                  &lt;/div&gt;
          &lt;/md-select&gt;
  </code></pre>
  
  <p>When I click on scroll bar the drop-down disappears and I am not able to select any option</p>