The compiler generates an error anyway if we would pass a sal_Unicode that is
outside the range of 'char' as the template parameter to OUStringLiteral1, so
if for some reason we would want cSequenceMarkSeparator to be outside of
ASCII, the code would need changes.

Change-Id: I1f6be560d3347cb957e1283dea2f7f7920d3aba7