I used a simple regular expression to identify the tests missing the call to setCaptionDisplay mode, git grep 'kind="captions" .* default>' so I missed several other occurrences of this issue. I now added git grep -l -e "default.*captions.*>" and git grep -l -e "captions.*default.*>" Besides, in media/track/track-cue-rendering-on-resize.html, I added setCaptionDisplayMode before the method is defined by video-test.js, so it wouldn't work. The new patch coming hopefully addresses all this issues.
Created attachment 209989 [details] Patch
Comment on attachment 209989 [details] Patch Clearing flags on attachment: 209989 Committed r154815: <http://trac.webkit.org/changeset/154815>
All reviewed patches have been landed. Closing bug.