winemac: Treat mouse moves in a window title bar as outside the window.

Don't queue mouse-moved events.  Reset the cursor.

dlls/winemac.drv/cocoa_app.m

@@ -1352,6 +1352,8 @@ - (void) handleMouseMove:(NSEvent*)anEvent
             windowUnderNumber = [NSWindow windowNumberAtPoint:point
                                   belowWindowWithWindowNumber:0];
             targetWindow = (WineWindow*)[NSApp windowWithWindowNumber:windowUnderNumber];
+            if (!NSMouseInRect(point, [targetWindow contentRectForFrameRect:[targetWindow frame]], NO))
+                targetWindow = nil;
         }
 
         if ([targetWindow isKindOfClass:[WineWindow class]])