I'm frequently seeing assertion failure in FrameLoader::checkLoadComplete(): ASSERT(m_client->hasWebView()); I couldn't make a test case, but the sequence of events if roughly as follows: - a subframe is detached (FrameLoader::detachFromParent is called); - this results in a Frame::pageDestroyed() call (which is a lie, as Page is not destroyed); - after a while, FrameLoader's checkTimer fires; - since Frame::m_page is null now, m_client->hasWebView() returns false. This doesn't always happen, because usually, Frame is destructed before checkTimer has a chance to fire, canceling the timer. But Frame destruction is not totally deterministic, and I see Frame::m_lifeSupportTimer timer sometimes keep it alive long enough for FrameLoader::checkTimer to fire.
<rdar://problem/7545095>
Created attachment 47147 [details] proposed fix
Committed <http://trac.webkit.org/changeset/53655>.