This properly handles null bytes that are expected
when converting between byte strings and Unicode.
It properly handles TransliterationFlags, which are
not a bitset.
In vbProperCase, it uses the correct method to
lowercase the string, working not only with ASCII.
Change-Id: I04e8cdca66ef9863a6516b15205a2a543ed97680
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/149224
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>
