macosx: fixed a logic problem which prevent the proper exit off the fullscreen...

macosx: fixed a logic problem which prevent the proper exit off the fullscreen mode when using the 64bit linked against the 10.7 SDK on 10.6 (close #6157)
(cherry picked from commit 4e7ebf8df7f57dafa2a9e4ad1486cc4908aa4e6f)

modules/gui/macosx/MainWindow.m

@@ -1339,8 +1339,11 @@ return YES;
     else
         [self makeFirstResponder: nil];
 
-    if (!b_videoPlayback && b_fullscreen && !b_nativeFullscreenMode)
-        [[VLCCoreInteraction sharedInstance] toggleFullscreen];
+    if (!b_videoPlayback && b_fullscreen)
+    {
+        if (!b_nativeFullscreenMode || !OSX_LION)
+            [[VLCCoreInteraction sharedInstance] toggleFullscreen];
+    }
 }
 
 - (void)resizeWindow