Fix the BackgroundMask again to prevent undefined behaviour.

Change-Id: I56b16845784a8679dbd67100024ac7acc3ddfba3
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

src/xmlpatterns/api/qcoloroutput_p.h

@@ -70,8 +70,8 @@ namespace QPatternist
             ForegroundShift = 10,
             BackgroundShift = 20,
             SpecialShift    = 20,
-            ForegroundMask  = ((1 << ForegroundShift) - 1) << ForegroundShift,
-            BackgroundMask  = ((1 << (sizeof(int) - BackgroundShift)) - 1) << BackgroundShift
+            ForegroundMask  = 0xffc00,
+            BackgroundMask  = 0xfff00000
         };
 
     public: