Qt4 embedded breakage has nothing to do with X11 afterall.

* A connect was called multiple times causing a wrong behaviour in the playlist.
* playlist_AddInput was replaced by playlist_Add to simplify code.
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

This is a VLC bug, not Qt4 version dependent.

The vout code invokes the Qt4 video widget through the Qt4 window
submodule. Hence, the video widget cannot call the vout window code.
This is where the embedded video crashes seem to come from.
Unfortunately, this commit trades the deadlock (on 1.0) or the crash
(on 0.9) for an assertion failure.

* Configuration aware to enable/disable (default enabled)
 * Filters available to ignore some patterns (using QRegExp)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

(bug at exit due to more generic problems with #2226 and #2227)

We really want plugins to resolve their VLC symbols against the already
loaded LibVLC core, rather than with their own version of it.
Performance benefit should be neglectible, if any.
Still, this will "fix" the plugin crash with static LibVLC builds (or
generate a due link-time error). Anyway, this is one step toward
supporting any form of static linking again.

Reported by Tobias Klein <tk@trapkit.de>

xinerama setup.