Focus the test on embedding QWindow: Remove the
NSToolBar code. Use standard NSApplication startup
code. Use winId() to access the NSView instead of
QPlatformNativeInterface (which is gui-private).
Rename Window -> RasterWindow.
Change-Id: Ie98cb73020d2721743bb665b89b17f07f2bf984b
Reviewed-by: Morten Johan Sørvig <morten.sorvig@theqtcompany.com>
