code: final void checkConformance(Node node, ErrorReporter errorReporter) {
      if (nodeClass.isAssignableFrom(node.getClass())) {
        doCheckConformance(nodeClass.cast(node), errorReporter);
      }
    }
docs: Checks whether the given node is relevant for this rule, and, if so, checks whether the node
  conforms to the rule. Intended to be called only from {@link SoyConformance}.