Import of web-animations-next-lite.min.js breaks source maps generation

[web-padawan]

Description

I try to implement source maps generation for my vulcanized Polymer project using gulp-sourcemaps. But parsing one of source maps in browser is being broken, because I use uglify to process web-animations-next-lite.min.js library code, which has already been minified and contains comments about its original source code.

There is no way to exclude this library from bundle, as I use web-component-shards as a bundling tool, which doesn't have an exclude option yet.

Expected outcome

neon-animated-pages should import unminified version web-animations-next-lite.js here:

<script src="../web-animations-js/web-animations-next-lite.min.js"></script>

So this will be up to user to decide whether this file should be minified or not.

Actual outcome

Failed to parse SourceMap: error in Chrome console.