Window that wraps around a raw window handle.
Users can safely assume that non-
0 fields are valid handles, and it is up to the
implementer of this trait to ensure that condition is upheld. However, It is entirely valid
behavior for fields within each platform-specific
RawWindowHandle variant to be
0, and appropriate checking should be done before the handle is used.
Despite that qualification, implementers should still make a best-effort attempt to fill in all available fields. If an implementation doesn't, and a downstream user needs the field, it should try to derive the field from other fields the implementer does provide via whatever methods the platform provides.
The exact handles returned by
raw_window_handle must remain consistent between multiple calls
raw_window_handle, and must be valid for at least the lifetime of the