Added WindowOverridesSystemGesturesHint to our window flags.

Change-Id: I42c3d3e5ef71960d16f85969b66380999fb15922
Reviewed-by: Samuel Rødal <samuel.rodal@nokia.com>

src/corelib/global/qnamespace.h

@@ -291,6 +291,7 @@ public:
         WindowShadeButtonHint = 0x00020000,
         WindowStaysOnTopHint = 0x00040000,
         WindowTransparentForInput = 0x00080000,
+        WindowOverridesSystemGestures = 0x00100000,
 
         CustomizeWindowHint = 0x02000000,
         WindowStaysOnBottomHint = 0x04000000,

src/corelib/global/qnamespace.qdoc

@@ -2062,6 +2062,10 @@
            even the softkeys are invisible i.e. the window is displayed with
            \c showFullscreen(). Only supported for Symbian.
 
+    \value WindowOverridesSystemGesturesHint Informs the window system that this window
+           implements its own set of gestures and that system level gestures, like for
+           instance three-finger desktop switching, should be disabled.
+
     \value WindowType_Mask  A mask for extracting the window type
                             part of the window flags.