ARROW-12393: [JS] [WIP] Drop closure compiler

[domoritz]

Before

693k -I Arrow.es5.min.js.map
 55k -I Arrow.externs.js
252k -I Arrow.js

After

1.2M -I Arrow.es5.min.js.map
310k -I Arrow.js

[github-actions]

https://issues.apache.org/jira/browse/ARROW-12393

[domoritz]

@trxcllnt I don't know much about gulp but this seems to run the same job twice when I run yarn build -t es5. How can I avoid that?

[domoritz]

Maybe it's worth trying to run closure over the es2015 sources as well (instead of removing closure) if the results are that much better 😆.

[alippai]

@domoritz closure compiler is discontinued, right? I can help looking into alternatives if you need any help with this issue.

[domoritz]

Thanks for offering to help. No, I don't think it's discontinued but it's a lot of work to keep it running for potentially small benefits so we are considering to remove it. We already use terser for all non es5 builds.

[alippai]

https://github.com/google/closure-compiler-npm/blob/master/packages/google-closure-compiler-js/readme.md, you are right, it looks like only the JS version is being discontinued

[domoritz]

Ah yes, I switched away from that last month when we updated to the latest closure compiler version.

[trxcllnt]

@domoritz it seems like not using Closure Compiler yields a bundle that's 58kb larger. Am I reading that correctly? What's the impact after compression? A larger bundle seems like a regression here.

[domoritz]

I haven't had the cycles to actually check. The bundles may not be correct yet so I wouldn't count on these numbers yet.

But if they are right, I wonder whether we should use closure for non es5 as well.

[domoritz]

Will redo and compare with updated terser as well.