This makes it easier to use third-party dependencies in this tool
(e.g. adding compression using algorithms not available in Python).
It is also much faster - locally js2c.py takes ~1.5s to generate the
output whereas this version takes ~0.1s - and consumes less memory
(~110MB v.s. 66MB).
This also modifies the js2c.py a bit to simplify the output, making
it easier to compare with one generated by the C++ version. Locally
the output from the two are identical. We'll remove js2c.py in a
subsequent commit when the C++ version is used by default.
PR-URL: https://github.com/nodejs/node/pull/46997
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
