Half of the tests expects strings in little endian byte order, half of
the tests expects byte order based on a current architecture, so it
obviously can't work on big endian machines. Wide char strings use
always little endian encoding since commit f722dc5. Use only strings
in little endian to make the tests endian-independent.
- Added missing ConvertFromUnicode checks
- If ConvertToUnicode allocates memory, guarantee the null termination
similar to ConvertFromUnicode's implementation
- Fixed some TestUnicodeConversion.c CTest return values
- Added some CTests for ConvertFromUnicode and ConvertToUnicode
- Misc code and protocol hardening fixes in the surrounding code regions
that have been touched
