HqlParser does not correctly negate EXISTS-nodes below an AND/OR

[csharper2010]

For the not explicitly handled cases in HqlParser.NegateNode, a new node is created but AND/OR do not correctly replace the children with the newly created ones.

This leads to wrong sql query.

Example base query (correctly handled):

SELECT COUNT(ROOT.Id)
FROM Entity AS ROOT
WHERE (
    EXISTS (FROM ChildEntity AS CHILD WHERE CHILD.Parent = ROOT)
    AND ROOT.Name = 'Test'
)

Example base query (wrong):

SELECT COUNT(ROOT.Id)
FROM Entity AS ROOT
WHERE NOT (
    EXISTS (FROM ChildEntity AS CHILD WHERE CHILD.Parent = ROOT)
    AND ROOT.Name = 'Test'
)

Pull request is created. Problem is obvious and the fix straightforward.
As someone has stated, a similar bugfix was made in Hibernate.

I would appreciate addition to next 5.4.x release.