audio: restore old speed change behavior

Don't attempt to resync after speed changes. Note that most other cases
of audio reinit (like switching tracks etc.) still resync, but other
code paths take care of setting the audio_status accordingly.

This restores the old behavior of not trying to fix audio desync, which
was probably changed with commit 261506e3.

Note that the code as of now wasn't even entirely correct, since the A/V
sync values are slightly shifted. The dsync depends on the audio buffer
size, so a larger buffer size will show more extreme desync. Also see
mplayer2 commit 213a224e, which should fixed this - it was not merged
into mpv, because it disabled audio for too long, resulting in a worse
user experience. This is similar to the issue this commit attempts to
fix.

Fixes: #1042 (probably)
CC: @mpv-player-stable
player: fix quit handling when seeking past EOF while paused

The player didn't quit when seeking past EOF in audio-only mode while
paused. The only case when we don't want to quit is when the last video
frame is displayed while paused.

This logic was probably broken a while ago, but I'm not exactly sure.

CC: @mpv-player/stable

Conflicts:
	player/playloop.c
x11: when using --wid, inherit event flags from parent window

When embedding a X window, it's hard to control whether it receives
mouse/keyboard input or not. It seems the X protocol itself makes this
hard (basically due to the outdated design mismatching with modern
toolkits), and we have to take care of these things explicitly.

Simply do this by manually querying and using the parent window event
flags.

This restores some MPlayer behavior (it doesn't add back exactly the
same code, but it's very similar).

This probably has some potential to interfere with libmpv embedding, so
bump the client API minor.

CC: @mpv-player/stable (if applied, client-api-changes.rst has to be
    adjusted to include the 0.5.2 release)
audio/out: prevent burning CPU when seeking while paused

The audio/video sync code in player/audio.c calls ao_reset() each time
audio decoding is entered, but the player is paused, and there would be
more than 1 sample to skip to make audio start match with video start.
This caused a wakeup feedback loop with push.c.

CC: @mpv-player/stable
playlist: don't add the base path twice

Loading a playlist with --playlist from a sub-directory added the
playlist's base path twice: one time in the playlist demuxer, and then
again in playlist_parse_file(). The latter function is used only for
--playlist, so it worked when loading the playlist directly.

(This is probably a mess-up when the MPlayer playlist parsers were
replaced with newer code.)

CC: @mpv-player/stable
man: fix a whole bunch of typos

Conflicts:
	DOCS/man/input.rst
	DOCS/man/options.rst
gl_wayland: fix crash after eglInitialze failed

Only execute most of the opengl termination procedure if we actually have an
egl context.
player: properly resume playlists loaded at runtime

If a playlist is loaded from the internal playlist (like
"mpv playlist.m3u"), then attempt to resume from it.

CC: @mpv-player/stable
path: remove XDG bullshit

Don't worry, your ~/.config/... paths are safe. This merely removes
handling of $XDG_CONFIG_DIRS for global paths.

Maybe there is a better solution for this, like still including the
"traditional" config dir. But I will leave the fine reading of this
(crappy) spec and fixing the code accordingly to someone else. So, if
anyone has interest in getting this behavior back, you will have to
write a patch. This patch should _also_ not break expected behavior.

Fixes #1060.
demux_mkv: allow up to 256 MB of extradata to make broken files work

What the flying fuck?

Unfortunately, these are already in the wild.

CC: @mpv-player/stable
build: handle insane libavcodec API bullshit

The oldest supported FFmpeg release doesn't provide
av_vdpau_alloc_context(). With these versions, the application has no
other choice than to hard code the size of AVVDPAUContext. (On the other
hand, there's av_alloc_vdpaucontext(), which does the same thing, but is
FFmpeg specific - not sure if it was available early enough, so I'm not
touching it.)

Newer FFmpeg and Libav releases require you to call this function, for
ABI compatibility reasons. It's the typcal lakc of foresight that make
FFmpeg APIs terrible. mpv successfully pretended that this crap didn't
exist (ABI compat. is near impossible to reach anyway) - but it appears
newer developments in Libav change the function from initializing the
struct with all-zeros to something else, and mpv vdpau decoding would
stop working as soon as this new work is relewased.

So, add a configure test (sigh).

CC: @mpv-player/stable
audio: fix obscure audio resync failure with timelines

Somehow, there was a larger misunderstanding in the code: ao_buffer
does not need to be preserved over audio reinit for proper support of
gapless audio. The actual AO internal buffer takes care of this.

In fact, preserving ao_buffer just breaks audio resync. In the ordered
chapter case, end_pts is used, which means not all audio data in the
buffer is played, thus some data is left over when audio decoding
resumes on the next segment. This triggers some code that aborts resync
if there's "audio decoded" (ao_buffer contains something), but no PTS
is known (nothing was actually decoded yet).

Simplify, and always bind the output buffer to the decoder.

CC: @mpv-player/stable (maybe)
player: check for null in resume config search

Signed-off-by: wm4 <wm4@nowhere>

CC: @mpv-player/stable
audio: correctly initialize output buffer

Just like the previous commit, this takes care of fallout from commit
7ab228, which fixed a bug, but introduced some new ones.

CC: @mpv-player/stable
audio/out: make EOF handling properly event-based

With --gapless-audio=no, changing from one file to the next apparently
made it hang, until the player was woken up by unrelated events like
input. The reason was that the AO doesn't notify the player of EOF
properly. the played was querying ao_eof_reached(), and then just went
to sleep, without anything waking it up.

Make it event-based: the AO wakes up the playloop if the EOF state
changes.

We could have fixed this in a simpler way by synchronously draining the
AO in these cases. But I think proper event handling is preferable.

Fixes: #1069
CC: @mpv-player/stable (perhaps)
stream_lavf: assume icy title data is terminated with ';'

Should fix #1071.
Release 0.5.2