If context_set_gl_context() fails, it marks the context as invalid.  It still
has an HDC, though, and context_update_window() would lose the reference to
it.

wbemprox: Add support for WBEM_FLAG_NONSYSTEM_ONLY and WBEM_FLAG_SYSTEM_ONLY in IWbemClassObject::GetNames.

It's not necessary.  Unlike with X11, on Mac OS X the pixel format doesn't affect
the properties of windows and views.  The pixel format is a property of the GL
context, which can attach to any view.