Correctly switch/revert from custom to bundled perms

[Fenn-CS]

We have a set custom permissions checkbox, that when selected should set the quick permissions settings to custom as well as show the custom permission settings.

When the checkbox is unchecked the quick permissions have to be reset to the default, bundledPermissions.ALL but also users can switch from custom permissions to bundled by just changing the radio select, hence we need a mechanism to set the permissions back to the correct fallback depending on where the user has toggled the the custom permission from.

The mechanism is revertSharingPermission and this commit, makes sure revert values are correctly set upon toggle.

Resolves : #40431

[blizzz]

/backport to stable27

[backportbot-nextcloud]

The backport to stable27 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable27
git pull origin stable27

# Create the new backport branch
git checkout -b fix/foo-stable27

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts. Resolve them.
git cherry-pick abc123

# Push the cherry pick commit to the remote repository and open a pull request
git push origin fix/foo-stable27

More info at https://docs.nextcloud.com/server/latest/developer_manual/getting_started/development_process.html#manual-backport

[backportbot-nextcloud]

The backport to stable27 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable27
git pull origin stable27

# Create the new backport branch
git checkout -b fix/foo-stable27

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts. Resolve them.
git cherry-pick abc123

# Push the cherry pick commit to the remote repository and open a pull request
git push origin fix/foo-stable27

More info at https://docs.nextcloud.com/server/latest/developer_manual/getting_started/development_process.html#manual-backport