In issue 672376, there's a crash due to the fact that there's no FrameHost already in FrameView::dispose(). It's believed that this is happening due to FrameView::dispose() being deferred by UpdateSuspendScope.

We should try to figure out what circumstances this is happening and fix it so this is no longer true. The easiest fix might be to just fix widget detachment to happen with frame detachment.