Transpiler from Dart to C++

Would be nice if this can be used to transpile a subset of Dart to C++.

Dart code -> [Dart source generator](https://pub.dartlang.org/packages/source_gen) -> [ebisu_cpp](https://github.com/patefacio/ebisu_cpp) -> C++

Could actually end up being very straight forward since most Dart code can be copied into C++ file and compiled with few modifications here and there.