Revert "flac packetizer: use the largest possible frame size"

This reverts commit 03e0644c82bf1dea96f8ade8829c2e1f360bd1ee.

Decoder needs single frames

Closes #9863
macosx: fix use after free for video effects string

This bug resulted in failure of setting more than one video effect
filter on mavericks.

close #9849
macosx: remove unneeded free