This change-set fixes a lot of windowing related bugs, especially with
regards to Windows 8.x apps running on Windows 10 (which was the driver for
this work). The primary fixes include:
* listed display modes were wrong, especially when launching apps into a
non-fullscreen space
* reported window flags were often wrong, especially on Windows 10
* fullscreen/windowed mode switches weren't failing (they are not
programmatically possible in Win 8.x apps).
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