Move DoNothing to upper level to reduce IntentManager's size

Change-Id: I8f1d6f6fbf44ee1ad6113a9b27a3ae0beef4cac1

+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.net.intent.impl;
+
+/**
+ * Represents a phase doing nothing.
+ */
+class DoNothing implements CompletedIntentUpdate {
+}

@@ -564,9 +564,6 @@ public class IntentManager
         }
     }
 
-    private class DoNothing implements CompletedIntentUpdate {
-    }
-
     // TODO: better naming
     private class WithdrawStateChange1 implements CompletedIntentUpdate {