A bug exists in the painting code in MediaPlayerPrivateQt which causes incorrect painting after changing size from a larger size to a smaller size.
Such a situation can occur in an HTML implementation of Fullscreen (when returning from fullscreen).
Created attachment 49555 [details]
Worlds simplest patch.
Comment on attachment 49555 [details]
Clearing flags on attachment: 49555
Committed r55302: <http://trac.webkit.org/changeset/55302>
All reviewed patches have been landed. Closing bug.