QShapedPixmapWindow: don't accept input focus

Inform the platform that it should not activate the window
when shown by setting Qt::WindowDoesNotAcceptFocus. This compliments
the already set Qt::WindowTransparentForInput, which specifies
that mouse/touch events should also pass through the window. In
other words, the window is just for showing output and should not
respond to input.

Change-Id: I3e90a28be2f2e27e2044effedf64f47c94a857a5
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>

src/gui/kernel/qshapedpixmapdndwindow.cpp

@@ -47,7 +47,7 @@ QShapedPixmapWindow::QShapedPixmapWindow()
     setFormat(format);
     setSurfaceType(RasterSurface);
     setFlags(Qt::ToolTip | Qt::FramelessWindowHint |
-                   Qt::X11BypassWindowManagerHint | Qt::WindowTransparentForInput);
+                   Qt::X11BypassWindowManagerHint | Qt::WindowTransparentForInput | Qt::WindowDoesNotAcceptFocus);
     create();
     m_backingStore = new QBackingStore(this);
 }