qtquick: Use Angle on Windows

It's aero-snap friendly. Otherwise shows black artifacts.
We can however use normal GL and use FramelessWindowhint instead

examples/qtquick/main.cpp

@@ -19,6 +19,7 @@
 
 int main(int argc, char *argv[])
 {
+    QGuiApplication::setAttribute(Qt::AA_UseOpenGLES);
     QGuiApplication app(argc, argv);
 
     QQuickView view;