Mac OS X gui: Make sure libvlc exit properly. Don't forward the closeVout: if the interface is dead.

* modules/codec/x264.c: Revert [16936] (temporarily fix x264 encoding on darwin/x86 by disabling all CPU optimisations) as this shouldn't be a problem anymore..

Mac OS X gui: Fix a double unlock issue, by making sure all timers are disabled when checking if we have to unlock. (Pointed by Felix Paul Kuhne)

* fixed support for future darwin releases on Intel. SDL, goom, gnutls and libpng still need to be fixed on both platforms.

- Fix illegal error return value for getnaminfo from [18812]
- Do not crash if the APIs are not available (*NULL) from [18812]

Should fix most Win32 resolution crashes
(if not already done in previous commits)

Mac OS X gui: Use a recursive lock to be able to trigger enter/leaveFullscreen in the middle of an enter/leaveFullscreen operation.

This is bound to crash.