title: jQuery's .val() returns different values for input elements with placeholder text in Firefox and Chrome
body: <p>Given the following HTML, I'm seeing different values being returned in Firefox and Chrome when using the latest jQuery:</p>
  
  <p>HTML:</p>
  
  <pre><code>&lt;input type="text" name="name" id="name" placeholder="Type Here"&gt;
  &lt;input type="email" name="email" id="email" placeholder="Type Here"&gt;
  </code></pre>
  
  <p>jQuery:</p>
  
  <pre><code>jQuery("#name").val();  // Returns "Type Here" in Chrome, blank in Firefox
  jQuery("#email").val(); // Returns "Type Here" in Chrome, blank in Firefox
  </code></pre>
  
  <p>In my opinion the above should return a blank string, since "Type here" is only placeholder text.</p>
  
  <p>Why the difference here?</p>