Fixes searching for native qt5 progs on cygwin and msys2

The reason for the issue is that on windows if there is a space in the path
or if the program is prepends with .exe and we specify the search PATH
in AC_PATH_PROGS we must enclose them in quotes or the program will not be
found.

For future reference, if anyone uses AC_PATH_PROGS please enclose defined
search paths (if you have any) in quotes
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

This mostly reverts commit 6a6c23bf.

Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

They are superseded by makeCurrent() and releaseCurrent().

The documentation promises that the picture is unlocked before it is
displayed, so actually do that.

Cc: Antti Ajanki <antti.ajanki@iki.fi>

date is always >= VLC_TS_INVALID

Original channels is under-specified in my opinion. If you know where
the design documentation is, please tell me.

Do like the other outputs do.

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Le 28/10/2014 23:11, Frédéric Yhuel a écrit :
>  static int MP4_NextBox( stream_t *p_stream, MP4_Box_t *p_box )
>  {
> -    MP4_Box_t box;
> +    MP4_Box_t box = {0};
>
>      if( !p_box )
>      {
>

Better fail early. (untested, no sample)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

picture_pool_NonEmpty() still won´t work quite right when the overflow
happens, but that function is a horrible dysfunctional hack anyway.

libgcc_s is still needed, for C++ modules

Gotta love libtool

Ref #12620