browser.php
protected function loadFrame($frames, $url, $parameters)
    {
        $page = $this->fetch($url, $parameters);
        $this->page->setFrame($frames, $page);

        return $page->getRaw();
    }
protected function loadFrame($frames, $url, $parameters)
    {
        $page = $this->fetch($url, $parameters);
        $this->page->setFrame($frames, $page);

        return $page->getRaw();
    }
Fetches a frame into the existing frameset replacing the original.

@param array $frames                    List of names to drill down.
@param string/SimpleUrl $url            Target to fetch as string.
@param SimpleFormEncoding $parameters   POST parameters.

@return string                          Raw content of page.