testDispose() {
    const mm = getModuleManager({'a': [], 'b': [], 'c': []});

    const moduleInfoA = mm.getModuleInfo('a');
    assertNotNull(moduleInfoA);
    const moduleInfoB = mm.getModuleInfo('b');
    assertNotNull(moduleInfoB);
    const moduleInfoC = mm.getModuleInfo('c');
    assertNotNull(moduleInfoC);

    mm.dispose();
    assertTrue(moduleInfoA.isDisposed());
    assertTrue(moduleInfoB.isDisposed());
    assertTrue(moduleInfoC.isDisposed());
  }
Make sure ModuleInfo objects in moduleInfoMap_ get disposed.