https://github.com/LykenSol/rust-demangle.c/pull/2 has been merged.
The main change from the PR as of me vendoring it is new support
for decoding and escaping UTF-8 string literals. In addition
clang-format was used for formatting the file.
This doesn't add support for the legacy symbol mangling scheme which is
currently the default pending support in tools for the v0 symbol
mangling scheme. The legacy symbol mangling scheme is similar enough to
C++'s symbol mangling scheme that demangling them using the C++
demangler generally produces readable symbols. The v0 scheme is entirely
custom and due to backreferences and encoding all generic arguments not
very readable when mangled, so supporting it is more important than
supporting the legacy scheme.
