private static boolean sendTombstonesInRIResults(final @NotNull InterestResultPolicy policy) {
    return policy == InterestResultPolicy.KEYS_VALUES;
  }
Determines whether keys for destroyed entries (tombstones) should be sent to clients in
register-interest results.

@return true if tombstones should be sent to the client
geode-core/src/main/java/org/apache/geode/internal/cache/tier/sockets/BaseCommand.java