LSP for goog.module navigation

[Rob Figueiredo]

Editors like VSCode provide helpful assistance around ES6 imports:

- You can navigate to an import 

- Hovering over an import shows the exports available

- Hovering over an imported symbol shows the definition of that symbol

Here's a screenshot:

I was wondering if anyone has looked into supporting that with goog.module? 

It should be possible to implement a language server module that implements that bit of analysis and use it for any editor:

https://code.visualstudio.com/api/language-extensions/language-server-extension-guide#implementing-a-language-server

[Rishipal Singh Bhatia]

Created a GutHub issue: https://github.com/google/closure-compiler/issues/3441