Fix broken build: s/assertNonNull/assertNotNull/

Change-Id: Id5943b8470f4b3b12912ff82710e8937ed8f7b2f
diff --git a/user/test/com/google/gwt/json/client/JSONTest.java b/user/test/com/google/gwt/json/client/JSONTest.java
index dd6440d..fcdda20 100644
--- a/user/test/com/google/gwt/json/client/JSONTest.java
+++ b/user/test/com/google/gwt/json/client/JSONTest.java
@@ -73,29 +73,29 @@
     if (expected.isArray() != null) {
       JSONArray expArray = expected.isArray();
       JSONArray actArray = actual.isArray();
-      assertNonNull(actArray);
+      assertNotNull(actArray);
       assertJSONArrayEquals(expArray, actArray);
     } else if (expected.isBoolean() != null) {
       JSONBoolean expBool = expected.isBoolean();
       JSONBoolean actBool = actual.isBoolean();
-      assertNonNull(actBool);
+      assertNotNull(actBool);
       assertEquals(expBool.booleanValue(), actBool.booleanValue());
     } else if (expected.isNull() != null) {
       assertNotNull(actual.isNull());
     } else if (expected.isNumber() != null) {
       JSONNumber expNum = expected.isNumber();
       JSONNumber actNum = actual.isNumber();
-      assertNonNull(actNum);
+      assertNotNull(actNum);
       assertEquals(expNum.doubleValue(), actNum.doubleValue());
     } else if (expected.isObject() != null) {
       JSONObject expObj = expected.isObject();
       JSONObject actObj = actual.isObject();
-      assertNonNull(actObj);
+      assertNotNull(actObj);
       assertJSONObjectEquals(expObj, actObj);
     } else if (expected.isString() != null) {
       JSONString expStr = expected.isString();
       JSONString actStr = actual.isString();
-      assertNonNull(actStr);
+      assertNotNull(actStr);
       assertEquals(expStr.stringValue(), actStr.stringValue());
     } else {
       fail("Unknown JSONValue " + expected);