void WebPluginScrollbarImpl::invalidateScrollbarRect(const IntRect& rect)
{
    WebRect webrect(rect);
    webrect.x += m_scrollbar->x();
    webrect.y += m_scrollbar->y();
    m_client->invalidateScrollbarRect(this, webrect);
}
void WebScrollbarImpl::invalidateScrollbarRect(WebCore::Scrollbar*, const WebCore::IntRect& rect)
{
    WebRect webrect(rect);
    webrect.x += m_scrollbar->x();
    webrect.y += m_scrollbar->y();
    m_client->invalidateScrollbarRect(this, webrect);
}