@Override
  public KeyInfo getKeyInfo(Object key, Object callbackArg) {
    return getKeyInfo(key, null, callbackArg);
  }
Changes the CustomExpiry for idleTimeout for values in the region

@param custom the new CustomExpiry
@return the old CustomExpiry
geode-core/src/main/java/org/apache/geode/internal/cache/PartitionedRegion.java