HttpObjectDecoder resetRequested not updated after reset

Motivation:
HttpObjectDecoder maintains a resetRequested flag which is used to determine if internal state should be reset when a decode occurs. However after a reset is done the resetRequested flag is not set to false. This leads to all data after this point being discarded.

Modifications:
- Set resetRequested to false when a reset is done

Result:
HttpObjectDecoder can still function after a reset.

codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java

@@ -509,6 +509,7 @@ public abstract class HttpObjectDecoder extends ByteToMessageDecoder {
             }
         }
 
+        resetRequested = false;
         currentState = State.SKIP_CONTROL_CHARS;
     }
 

codec-http/src/test/java/io/netty/handler/codec/http/HttpContentDecoderTest.java

@@ -18,6 +18,8 @@ package io.netty.handler.codec.http;
 
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
 import io.netty.channel.embedded.EmbeddedChannel;
 import io.netty.handler.codec.compression.ZlibCodecFactory;
 import io.netty.handler.codec.compression.ZlibDecoder;
@@ -30,9 +32,16 @@ import org.junit.Test;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Queue;
+import java.util.concurrent.atomic.AtomicReference;
 
-import static org.hamcrest.CoreMatchers.*;
+import static org.hamcrest.CoreMatchers.instanceOf;
-import static org.junit.Assert.*;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
 
 public class HttpContentDecoderTest {
     private static final String HELLO_WORLD = "hello, world";
@@ -217,6 +226,60 @@ public class HttpContentDecoderTest {
         assertFalse(channel.finish());
     }
 
+    @Test
+    public void testExpectContinueResetHttpObjectDecoder() {
+        // request with header "Expect: 100-continue" must be replied with one "100 Continue" response
+        // case 5: Test that HttpObjectDecoder correctly resets its internal state after a failed expectation.
+        HttpRequestDecoder decoder = new HttpRequestDecoder();
+        final int maxBytes = 10;
+        HttpObjectAggregator aggregator = new HttpObjectAggregator(maxBytes);
+        final AtomicReference<FullHttpRequest> secondRequestRef = new AtomicReference<FullHttpRequest>();
+        EmbeddedChannel channel = new EmbeddedChannel(decoder, aggregator, new ChannelInboundHandlerAdapter() {
+            @Override
+            public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
+                if (msg instanceof FullHttpRequest) {
+                    if (!secondRequestRef.compareAndSet(null, (FullHttpRequest) msg)) {
+                        ((FullHttpRequest) msg).release();
+                    }
+                } else {
+                    ReferenceCountUtil.release(msg);
+                }
+            }
+        });
+        String req1 = "POST /1 HTTP/1.1\r\n" +
+                "Content-Length: " + (maxBytes + 1) + "\r\n" +
+                "Expect: 100-continue\r\n" +
+                "\r\n";
+        assertFalse(channel.writeInbound(Unpooled.wrappedBuffer(req1.getBytes(CharsetUtil.US_ASCII))));
+
+        FullHttpResponse resp = channel.readOutbound();
+        assertEquals(HttpStatusClass.CLIENT_ERROR, resp.status().codeClass());
+        resp.release();
+
+        String req2 = "POST /2 HTTP/1.1\r\n" +
+                "Content-Length: " + maxBytes + "\r\n" +
+                "Expect: 100-continue\r\n" +
+                "\r\n";
+        assertFalse(channel.writeInbound(Unpooled.wrappedBuffer(req2.getBytes(CharsetUtil.US_ASCII))));
+
+        resp = channel.readOutbound();
+        assertEquals(100, resp.status().code());
+        resp.release();
+
+        byte[] content = new byte[maxBytes];
+        assertFalse(channel.writeInbound(Unpooled.wrappedBuffer(content)));
+
+        FullHttpRequest req = secondRequestRef.get();
+        assertNotNull(req);
+        assertEquals("/2", req.uri());
+        assertEquals(10, req.content().readableBytes());
+        req.release();
+
+        assertHasInboundMessages(channel, false);
+        assertHasOutboundMessages(channel, false);
+        assertFalse(channel.finish());
+    }
+
     @Test
     public void testRequestContentLength1() {
         // case 1: test that ContentDecompressor either sets the correct Content-Length header