It is a manual backport of:
- [9b8c543c] Subtitles accuracy
- [9c462ffb] Ephemere destruction
- [fabf2399] Fixes for previous commits

It does not changes existing functions, but add 2 new ones.

(cherry picked from commit 72741d68)
Signed-off-by: Rémi Duraffort <ivoire@videolan.org>

non BOS headers for (Vorbis, Theora, Speex, Kate) do not have to be on separate pages, so avoid flushing before the last header
Signed-off-by: Laurent Aimar <fenrir@videolan.org>
(cherry picked from commit f87986e4)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Laurent Aimar <fenrir@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>
(cherry picked from commit a077fb25)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Now seeking and skipping behave exactly the same.
It also allows forward seeking in non seekable stream by reading the data.
It closes #2994.
As it is a critical section of code, it must be carefully tested.
(cherry picked from commit fa43c146)

It is a partial backport of [30086cdc]

It is a partial backport of [30086cdc]

(cherry picked from commit 6456512f)

It avoids loosing subtitles with the messages
"main subpicture error: subpicture heap full".
(cherry picked from commit 34f25416)

It also avoid useless mdate() when decoding audio.
(cherry picked from commit 87129938)

(cherry picked from commit 6088f39f)

This will still assert in debug build due to a core bug

EXTRA_DATA doesn't seem to be a "primary" even if DATA is and EXTRA is a valid prefix.
Also i don't think .vlt are often rebuilt so it should be in clean rather than mostly clean
(cherry picked from commit 4fdaf53d)

dialog_ProgressCreate can return NULL. For this case,
only deal with the result if it is not NULL.
Signed-off-by: Rémi Duraffort <ivoire@videolan.org>
(cherry picked from commit 29e7fc71)
Signed-off-by: Rémi Duraffort <ivoire@videolan.org>

(cherry picked from commit 5c9b0299)
Signed-off-by: Rémi Duraffort <ivoire@videolan.org>

(cherry picked from commit 4df6f959)
Signed-off-by: Rémi Duraffort <ivoire@videolan.org>

Signed-off-by: Rémi Duraffort <ivoire@videolan.org>
(cherry picked from commit f9b30861)
Signed-off-by: Rémi Duraffort <ivoire@videolan.org>

(cherry picked from commit 56dc82ed)
Signed-off-by: Rémi Duraffort <ivoire@videolan.org>

Work around the missing PathIsNetworkPathW() function...
(cherry picked from commit 1e1269ba)

(cherry picked from commit f29f7e10)

Pointed-out-by: tixxDZ <tixxdz@gmail.com> - DZCORE Labs, Algeria
(cherry picked from commit dc74600c)

(cherry picked from commit 9eb5b0ce)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

This is not ready yet.
(cherry picked from commit 1f952b3d)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

The .dll is still a bit big, because of static linking to libiconv, I think
(cherry picked from commit eaa615ce)

Conflicts:

	extras/contrib/src/Makefile

should fix bug #2947 ,now it scrolls to new item when theres actual
input-change, not just data changed.
(cherry picked from commit 5f81bec5)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>