As MediaControlRootElement decides whether it will display timeline according to the return value of RenderTheme's hasOwnDisabledStateHandlingFor(), RenderThemeEfl has to implement this function.
Created attachment 99590 [details] Patch
LGTM.
Comment on attachment 99590 [details] Patch Clearing flags on attachment: 99590 Committed r90382: <http://trac.webkit.org/changeset/90382>
All reviewed patches have been landed. Closing bug.