An example that uses the C API of the Dart VM.
The example shows how to pass an object from the Dart heap to native code and
hold on to it via a PersistentHandle. For more documentation about handles,
and the other C API features refer to the documentation in the header files.
Run tests with dart --enable-experiment=native-assets test.
It would be better to receive a path the include folder containing the C API
rather than having to copy it into the src/ directory.