Enable renaming input map arguments

[Noam Helfman]

Following up on Re-add Minification Mapping Input Suggestion · Issue #4097 · google/closure-compiler (github.com) I would like to submit the change to re-enabled renaming input maps for properties and variables. The guideline for sumitting changes suggests I should post to the group before issuing a PR.

I have done extensive testing locally with such change and it appears to have major positive impact on ensure renaming is consistent between 2 build versions of our app.

This is critical for me to be able to effective enable and support Compression Dictionary Transport which requires creating a a bortli diff between to JS file versions. Without using input maps, the brotli diff is about 45% of original file even when only minmal real changes occured between versions.

When passing input maps of previous build as part of compilation, I was able to see a brotli diff of only 10% which is a significant size reduction.

The change is very simple and just re-add the command line options in CommandLineRunner.java (attached patch file).

Please let me know if there is any concern with me proceeding with this.

Thanks,

Noam

[Bradford Smith]

I think this looks like quite a reasonable PR.

Go ahead and create it.

Thanks for asking.

Bradford

[Noam Helfman]

Here is the pull request: https://github.com/google/closure-compiler/pull/4155