YARN-11247. Remove unused classes introduced by YARN-9615. (#4720)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/metrics/DisableEventTypeMetrics.java

@@ -1,42 +0,0 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you 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.apache.hadoop.yarn.metrics;
-
-import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.metrics2.MetricsCollector;
-import org.apache.hadoop.metrics2.annotation.Metrics;
-
-@InterfaceAudience.Private
-@Metrics(context="yarn")
-public class DisableEventTypeMetrics implements EventTypeMetrics {
-  @Override
-  public void increment(Enum type, long processingTimeUs) {
-    //nop
-    return;
-  }
-  @Override
-  public void getMetrics(MetricsCollector collector, boolean all) {
-    //nop
-    return;
-  }
-
-  @Override
-  public long get(Enum type) {
-    return 0;
-  }
-}