From https://bugs.gentoo.org/show_bug.cgi?id=218105: FFmpeg recently changed all the include paths. Every application using it should update. May need some automagic to determine ffmpeg version though.
I'm closing this as WONTFIX, for the following reasons: 1) The 0.6 branch of Swfdec is stable, so no API changes will occur. 2) The 0.7 branch will probably remove ffmpeg support rather sooner than later, so it's not worth fixing it.
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