- fixed 3135642 -- ad frames are missing at channels.netscape.com

        * khtml/rendering/render_frames.cpp: (RenderPartObject::updateWidget): Updated to use the
	same rule as Mozilla: Empty URL for an iframe means "about:blank".

        * khtml/ecma/kjs_window.cpp: (Window::isSafeScript): Loosen things so that it's safe for
	a frame to manipulate an empty child frame, as well as an empty opened window. Also remove
	the useless check for an empty document -- it never happens in practice.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@3213 268f45cc-cd09-0410-ab3c-d52691b4dbfc