Right now, getting to the WebFrameWidget from core is pretty awkward. Code usually does this by bouncing through ChromeClient. Since ChromeClient is page-associated, the code that does this needs to pass a LocalFrame, which ChromeClient uses to look up the WebLocalFrame local root, then the WebFrameWidget, and finally the WebWidgetClient.

It would be nice if we could just talk to WebWidgetClient directly from core (and have each LocalFrame save a pointer to the correct WebWidgetClient to talk to, so we don't need to traverse the frame tree each time).