title: switch frame by class name webdriverio
body: <p>I'm try switch frame, but they ID and Name attribute is dynamic. I'm used webdriverio. Can i use class name? any ideas?</p>
  
  <pre><code>&lt;iframe id="n33l4d68f0xr" class="KA-JQ" name="n33l4d68f0xr" src="https://docs.google.com/picker?protocol=gadgets&amp;origin=https%3A%2F%2Fmail.google.com&amp;hl=en&amp;hostId=gmail-to&amp;multiselectEnabled=true&amp;navHidden=true&amp;dff=0&amp;authuser=0&amp;title=Select%20contacts&amp;relayUrl=https%3A%2F%2Fmail.google.com%2Ffavicon.ico&amp;nav=((%22contacts%22))&amp;rpctoken=fmac4onpwdet&amp;rpcService=n33l4d68f0xr" tabindex="0" frameborder="0"&gt;
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