// notifications for all of them.
    for (int i = 0; i < nSeededEntries; i++) {
      assertEquals("b" + i, removalNotifications.get("b" + i));
    }

    // Each of the values added to the map should either still be there, or have seen a removal
    // notification.
    assertEquals(expectedKeys, Sets.union(cache.asMap().keySet(), removalNotifications.keySet()));

    // notifications for all of them.
    for (int i = 0; i < nSeededEntries; i++) {
      assertEquals("b" + i, removalNotifications.get("b" + i));
    }

    // Each of the values added to the map should either still be there, or have seen a removal
    // notification.
    assertEquals(expectedKeys, Sets.union(cache.asMap().keySet(), removalNotifications.keySet()));