it seems it only produces an error in a non sourced environment

Old work in progress by sberg, committed by tml.

Removed uses of rtl::O[U]String[Buffer]::operator sal_{char|Unicode} const *() in Mac OS X only code.

Added #include "unotest/oustringostreaminserter.hxx" back in (will be needed once rtl::OUString::operator sal_Unicode const *() is removed); made tools explicitly depend on unotest.