code: private boolean allDefinitionsEquivalent(Collection<Node> definitions) {
      Node first = null;
      for (Node n : definitions) {
        if (first == null) {
          first = n;
        } else if (!compiler.areNodesEqualForInlining(first, n)) {
          return false;
        } // else continue
      }
      return true;
    }
docs: Given a set of method definitions, verify they are the same.