MacOS GUI: Tie display fade to "Black out" preference

Change the MacOS GUI to trigger the fade of all the displays to black
when entering & leaving full screen mode only if the "Black out other
displays" preference is set.
Signed-off-by: Felix Paul Kühne <fkuehne@videolan.org>

modules/gui/macosx/embeddedwindow.m

@@ -479,8 +479,11 @@
              * simply fade the display */
             CGDisplayFadeReservationToken token;
 
-            CGAcquireDisplayFadeReservation(kCGMaxDisplayReservationInterval, &token);
+            if( blackout_other_displays )
+            {
+                CGAcquireDisplayFadeReservation( kCGMaxDisplayReservationInterval, &token );
                 CGDisplayFade( token, 0.5, kCGDisplayBlendNormal, kCGDisplayBlendSolidColor, 0, 0, 0, YES );
+            }
 
             if ([screen isMainScreen])
                 SetSystemUIMode( kUIModeAllHidden, kUIOptionAutoShowMenuBar);
@@ -494,8 +497,11 @@
 
             [o_fullscreen_window setFrame:screen_rect display:YES];
 
+            if( blackout_other_displays )
+            {
                 CGDisplayFade( token, 0.3, kCGDisplayBlendSolidColor, kCGDisplayBlendNormal, 0, 0, 0, NO );
-            CGReleaseDisplayFadeReservation( token);
+                CGReleaseDisplayFadeReservation( token );
+            }
 
             /* Will release the lock */
             [self hasBecomeFullscreen];
@@ -597,6 +603,7 @@
 {
     NSMutableDictionary *dict1, *dict2;
     NSRect frame;
+    BOOL blackout_other_displays = config_GetInt( VLCIntf, "macosx-black" );
 
     [self lockFullscreenAnimation];
 
@@ -619,8 +626,11 @@
         * simply fade the display */
         CGDisplayFadeReservationToken token;
 
-        CGAcquireDisplayFadeReservation(kCGMaxDisplayReservationInterval, &token);
+        if( blackout_other_displays )
+        {
+            CGAcquireDisplayFadeReservation( kCGMaxDisplayReservationInterval, &token );
             CGDisplayFade( token, 0.3, kCGDisplayBlendNormal, kCGDisplayBlendSolidColor, 0, 0, 0, YES );
+        }
 
         [[[[VLCMain sharedInstance] controls] fspanel] setNonActive: nil];
         SetSystemUIMode( kUIModeNormal, kUIOptionAutoShowMenuBar);
@@ -632,8 +642,12 @@
          * here */
         b_window_is_invisible = YES;
 
+        if( blackout_other_displays )
+        {
             CGDisplayFade( token, 0.5, kCGDisplayBlendSolidColor, kCGDisplayBlendNormal, 0, 0, 0, NO );
-        CGReleaseDisplayFadeReservation( token);
+            CGReleaseDisplayFadeReservation( token );
+        }
+
         return;
     }