fix: don't let uglify-es inline functions with arguments

Fixes #346. This is a workaround for a bug in uglifyjs2 (mishoo/UglifyJS#2842), which can cause name collisions when a function with arguments is inlined. This can cause an unintended shadowing of a `var` or `let`, or a `TypeError: Assignment to constant variable` in case of a `const`.

Author: ppvg

packages/react-scripts/config/webpack.config.prod.js

@@ -315,6 +315,9 @@ module.exports = {
  // Pending further investigation:
  // https://github.com/mishoo/UglifyJS2/issues/2011
  comparisons: false,
+ // Don't inline functions with arguments, to avoid name collisions:
+ // https://github.com/mishoo/UglifyJS2/issues/2842
+ inline: 1,
  },
  mangle: {
  safari10: true,