It's completely unnecessary, since QFileInfo will query the file system
anyway and that has a much better view of what is normalized and what
isn't. More importantly, this fixes the mistake in failing to normalize
properly in removePaths(), which removed the ending slash of a root
directory such as "C:\\". That caused the path to become "C:", which
QFileInfo interprets as "current path on drive C:".
[ChangeLog][QtCore][QFileSystemWatcher] Fixed a bug that prevented
removePaths() from removing the root of a drive on Windows.
Fixes: QTBUG-110986
Pick-to: 5.15 6.2 6.4 6.5
Change-Id: I9671dee8ceb64aa9b9cafffd17419b6d69670876
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
6d17697913