In the constructor of IterationManager, removed the check for null argument (already carried out in the constructor of Incrementor).

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1353586 13f79535-47bb-0310-9956-ffa450edef68

src/main/java/org/apache/commons/math3/util/IterationManager.java

@@ -58,9 +58,6 @@ public class IterationManager {
      */
     public IterationManager(final int maxIterations,
                             final Incrementor.MaxCountExceededCallback callBack) {
-        if (callBack == null) {
-            throw new NullArgumentException();
-        }
         this.iterations = new Incrementor(maxIterations, callBack);
         this.listeners = new CopyOnWriteArrayList<IterationListener>();
     }