Missing code completions on Android code for a plugin project

The Android code for an app project (i.e., standard `flutter create` template) can be edited if configured using [these steps](https://flutter.io/intellij-ide/#edit-android-code).

This doesn't appear to work for plugin projects:

1. `flutter create --plugin myplugin`
1. `cd myplugin`
1. `idea .`

=>

Dart analysis works as expected on `lib/main.dart`

Analysis appears to work for Java code, but code completions do not:

1. Open `android/src/.../MypluginPlugin.java`
1. In line 28, type `result.`

=> no completions