title: Ext js Numberfield in Chrome device Emulator allow type "e" (exponential)
body: <p>I am having an issue with Ext JS number field.
  It is allowed to type the letter &quot;e&quot; in a number field component when I am using a device in google chrome emulator.</p>
  <p>Steps to reproduce the behavior:</p>
  <ol>
  <li>Enter in this fiddle: <a href="https://fiddle.sencha.com/#view/editor&amp;fiddle/36eh" rel="nofollow noreferrer">https://fiddle.sencha.com/#view/editor&amp;fiddle/36eh</a></li>
  <li>Press F12 to open inspect mode.</li>
  <li>Click on the Device icon to change to device mode.</li>
  <li>Click to Run the fiddle again.</li>
  <li>Type letter &quot;e&quot; in the number field component.</li>
  <li>Verify that was possible to inform the letter &quot;e&quot; in device mode.</li>
  </ol>
  <p>Have you guys ever seen this issue?</p>
  <p>Thanks,
  Renato Carvalho.</p>