JS properties named '_xyz' are broken by minification.

[mikelehen]

If our code defines a property named _xyz, e.g.:

public get _databaseId(): DatabaseId {
  return this._config.databaseId;
}

Then usages of the property get minified in our build, but the actual property does not, leading to runtime errors.

I had to work around this (see #197) to fix a customer-reported bug in the minified build.

[google-oss-bot]

Hey there! I couldn't figure out what this issue is about, so I've labeled it for a human to triage. Hang tight.

[google-oss-bot]

Hmmm this issue does not seem to follow the issue template. Make sure you provide all the required information.

[jshcrowthe]

This was done to be super aggressive about generating our CDN bundles. Until we no longer want to support a "prod ready" CDN build, allowing property mangling is something that we'd like to support.