title: Selenium WebDriver get Current frame before switch
body: <p>I have a custom action to find elements, by switching in the certain iFrame.
  It uses the following native action:
  <code>driver.switchTo().frame(requested_frame)</code>
  Currently I am switching back to the default content every-time before switch to the exact iframe.</p>
  
  <p>Now I need to improve it's performance by following scnario:</p>
  
  <ul>
  <li>Check the current content/frame</li>
  <li>if <code>requested_frame=currentFrame</code> then No need to switch</li>
  <li>if <code>requested_frame=null</code> then switch to default (if <code>currentFrame=default</code> then again no need to switch)</li>
  <li>if <code>requested_frame!=null &amp;&amp; requested_frame!=currentFrame</code> then switch to default, and switch to <code>requested_frame</code> frame.</li>
  </ul>
  
  <p>So all I need now is to get the Current Frame. Is there any way I can get it? </p>