code: AbstractJcrNode node( CachedNode cachedNode,
                            AbstractJcrNode.Type expectedType ) {
          return node(cachedNode, expectedType, null);
      }
docs: Obtain the {@link Node JCR Node} object for the node with the supplied key.
  
  @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
  @return the JCR node; never null
  @see #node(CachedNode, Type, NodeKey)