When we get an orientation event we don't care about keeping track of the
configuration changes, but actually we can consider the new configuration
just a variant of the previous one, adapted to floating device hardware
events, so we only want to apply it if possible, but we don't want to keep
a record of it for reverting capabilities.
Doing that would in fact, break the ability of reverting back to an actual
temporary or persistent configuration.
For example when device orientation events happen while we're waiting for
an user resolution change confirmation, we would save our new rotated
configuration in the history, making then impossible to revert back to
the original persistent one.
So in such case, don't keep track of those configurations in the history,
but only keep track of the last one as current, checking whether the
new current is child or sibling of the previously one.
Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1221
Related to: https://gitlab.gnome.org/GNOME/mutter/-/issues/646
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1233>
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