code: public boolean rowContainsKey(String key) {
          String resolvedKey = resolveRowKey(key);
          return rowMap.containsKey(resolvedKey)
                  || parent != null && parent.rowContainsKey(resolvedKey);
      }
docs: Returns {@code true} if this map or a parent map - if any - contains a RowSpec mapping for
  the specified key.
  
  @param key key whose presence in this LayoutMap chain is to be tested.
  @return {@code true} if this map contains a row mapping for the specified key.
  
  @throws NullPointerException if the key is {@code null}.
  
  @see Map#containsKey(Object)