Signed-off-by: Rémi Denis-Courmont <rdenis@simphalempin.com>

sacred knowledge shouldnt be forgotten by future generations of VLC
devs.

It it locked when returning from vlc_object_wait/vlc_cond_wait

Conflicts:

	src/input/decoder.c

This reverts commit 3c9681e1.
It breaks DMO/Qt decoding. It can be commited again when a fix
is found.

This removes a silly error message.

It will work most of the time.
Subtitle are not correctly handled.
It will be ignored if no video.