Suggestion: support es modules .mjs file with mime-type application/javascript

Hi all.

Node.js decided to use .mjs file extension for ES Moduels.

https://github.com/nodejs/node-eps/blob/master/002-es-modules.md#32-determining-if-source-is-an-es-module

this cause developer will write es modules in .mjs file and also serve to browser as is.

so http server who determine content-type via file extension should support .mjs avoid to be content-type: octet-stream

the mime type for .mjs are same as .js as follow.

https://github.com/nodejs/node-eps/blob/master/002-es-modules.md#321-mime-of-mjs-files

so rails/actionpack/lib/action_dispatch/http/mime_types.rb better to add following line


Mime::Type.register "text/javascript", :js, %w( application/javascript application/x-javascript )

+ Mime::Type.register "text/javascript", :mjs, %w( application/javascript application/x-javascript )

any comments are welcome.

thanks

Jxck