char16, char32, and wchar_t were previously broken. If you had a simple variable like wchar_t x = L'1' and wrote p x LLDB would output (wchar_t) x = 1\0. This is because it was using eFormatChar with a size of 2. What we needed was to introduce a special format specifically for wchar_t. The only valid sizes of wchar_t on all existing compilers are 2 and 4, so there's no real point trying to handle sizes of 1 and 8.
Along the way, I accidentally stumbled across the reason that references that char16 and char32 types were also formatting incorrectly, so I fixed that as well.