Add a workaround for the Firefox local swf-file bug
(explained in https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1335388).
Except this commit does not yet include the workaround.
Add the actual workaround for the Firefox local swf-file bug.
From
http://askubuntu.com/questions/478169/why-cant-firefox-run-local-swf-files.