Add some simple unit tests for goaway frames.

These required several changes to HTTP/2 processing
- tracking pings to match ACKs with original pings
- tracking round trip time
- regular (every 10s) pings to track changes to round trip time
- differentiate between pausing and paused states

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1688655 13f79535-47bb-0310-9956-ffa450edef68

java/org/apache/coyote/http2/HeaderSink.java

@@ -0,0 +1,32 @@
+/*
+ *  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.coyote.http2;
+
+import org.apache.coyote.http2.HpackDecoder.HeaderEmitter;
+
+/**
+ * Purpose of this class is to silently swallow any headers. It is used once
+ * the connection close process has started if headers for new streams are
+ * received.
+ */
+public class HeaderSink implements HeaderEmitter {
+
+    @Override
+    public void emitHeader(String name, String value, boolean neverIndex) {
+        // NO-OP
+    }
+}