False negative: Nullness Checker allows leaking implicit `@UnderInitialization this` to inner class c'tor

Nullness Checker apparently does not verify the implicit reference to enclosing class instance.

Let's consider the following class:

class SampleClass {
  final InnerClass inner;
  final String foo;

  SampleClass() {
    this.inner = new InnerClass();
    this.inner.bar(); /// WHOOPS... NPE
    this.foo = "Hello world";
  }

  class InnerClass {
    String bar() {
      return foo.substring(1);
    }
  }
}

This compiles with no error, despite clearly leading to an NPE in the runtime.

A nearly equivalent snippet that uses a static nested class instead:

class SampleClass {
  final InnerClass inner;
  final String foo;

  SampleClass() {
    this.inner = new InnerClass(this); // Ok, NullnessChecker raises an error
    this.inner.bar();
    this.foo = "Hello world";
  }

  static class InnerClass {
    SampleClass outer;
    InnerClass(SampleClass outer) {
      this.outer = outer;
    }
    String bar() {
      return outer.foo.substring(1);
    }
  }
}

fails as expected on nullness:assignment.type.incompatible and argument.type.incompatible.