Parsing untrustworthy data is a major source of security bugs, and it's therefore against Chromium rules to do it in the browser process unless you can use a memory safe language.
For teams building browser process features which need to handle untrustworthy data, they usually have to do the parsing in a utility process which incurs a performance overhead and adds engineering complexity.
The Chrome security team is working to make a cross-platform memory safe language available to Chromium developers. This document describes how to use that language in Chromium. The language, at least for now, is Rust.
Support for Rust in Chromium is experimental. We appreciate your help in these experiments, but please remember that Rust is not supported for production use cases.
That said, if presence of Rust would make your feature easier, we are keen for you to join in our experiments. Here's how. Please also let us know your interest via email@example.com.