/// <summary>
 /// Called when the browser component is requesting focus.
 /// |source| indicates where the focus request is originating from.
 /// Return false to allow the focus to be set or true to cancel setting the focus.
 /// </summary>
 protected virtual bool OnSetFocus(CefBrowser browser, CefHandlerFocusSource source)
 {
     return(false);
 }
 /// <summary>
 /// Called when the browser component is requesting focus.
 /// |source| indicates where the focus request is originating from.
 /// Return false to allow the focus to be set or true to cancel setting the focus.
 /// </summary>
 protected virtual bool OnSetFocus(CefBrowser browser, CefHandlerFocusSource source)
 {
     return false;
 }