2.2.2 breaks enums in GTS files

[Techn1x]

First mentioned here #38 (comment)

If an enum is defined and used in a component (within the same file)

// app/components/alert.gts
export enum AlertType {
  Information = 'information',
  Warning = 'warning',
  Critical = 'critical',
  Success = 'success',
  NewFeature = 'new-feature',
}

export component Alert: TOC = <template>
  {{#if (eq @type AlertType.Warning)}}
    ...
  {{else if ...}}
    ...
  {{/if}}
</template>

produces runtime error

Uncaught (in promise) Error: Attempted to resolve a value in a strict mode template, but that value was not in scope: AlertType

However it will work if any of these changes are made;

• if the enum is defined in some other file and imported in
• if the enum is set as a property in the component, and that is used in the template

[NullVoxPopuli]

issue still present with content-tag 2.0.3 and babel-plugin-ember-template-compilation 2.3.0