Review

Load of known null value as argument.

• superfluous/value_or_state

com/google/javascript/jscomp/graph/LinkedDirectedGraph.java

getDirectedPredNodes(DiGraphNode)

class LinkedDirectedGraph {
  @Override
  public List<DiGraphNode<N, E>> getDirectedPredNodes(
      DiGraphNode<N, E> dNode) {
    if (dNode == null) {
      throw new IllegalArgumentException(dNode + " is null");
    }
    List<DiGraphNode<N, E>> nodeList = Lists.newArrayList();
    for (DiGraphEdge<N, E> edge : dNode.getInEdges()) {
      nodeList.add(edge.getSource());
    }
    return nodeList;
  }

}