code: AbstractJcrNode node( CachedNode cachedNode,
                            AbstractJcrNode.Type expectedType,
                            NodeKey parentKey ) {
          return node(cachedNode, cache, expectedType, parentKey);
      }
docs: Obtain the {@link Node JCR Node} object for the cached node and this session's cache
  
  @param cachedNode the cached node; may not be null
  @param expectedType the expected implementation type for the node, or null if it is not known
  @param parentKey the node key for the parent node, or null if the parent is not known
  @return the JCR node; never null