ember-cli-babel: Another _Ember is undefined error

Ya, sorry for this taking so long. It took a little while to figure out which specific babel plugins were mutating the nodes, and I only discovered that using the shared AST nodes was causing an issue due to stepping through the tranpsilation process.

#348 should land and be released as 7.20.5 soon.

OK, that sounds a lot like the scenario that @sandydoo called out and provided a reproduction for. I’ll be looking into it this afternoon.

https://github.com/babel/ember-cli-babel/releases/tag/v7.20.5 is published now with the updates from https://github.com/ember-cli/babel-plugin-ember-modules-api-polyfill/pull/109. I tried to explain exactly what was going on in #348 and https://github.com/ember-cli/babel-plugin-ember-modules-api-polyfill/pull/109.

Note: the actual fix was in https://github.com/ember-cli/babel-plugin-ember-modules-api-polyfill/pull/109, so you can almost certainly get these fixes without being on ember-cli-babel@7.20.x, but in order to do so you’d need to ensure your lockfile doesn’t keep the babel-plugin-ember-modules-api-polyfill pinned.

For example, for yarn users you can do:

• add a resolution for babel-plugin-ember-modules-api-polyfill to use 2.13.4
• run yarn
• remove the resolution
• run yarn again

@rwjblue if I turn on

if (isCI || isProduction) {
  browsers.push('ie 11');
}

I have the next error:

ReferenceError: _Ember is not defined
    at configurable (/usr/src/fastboot/dist/assets/addon-tree-output/torii/configuration.js:13:1)```

I use torii: 0.9.6 which depends on "ember-cli-babel": "^6.3.0". But I have a lot of libraries which depend on "ember-cli-babel": "^6.3.0"