[#1295] Make sure retain(..) returns the correct WebSocketFrame type

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/BinaryWebSocketFrame.java

@@ -58,4 +58,16 @@ public class BinaryWebSocketFrame extends WebSocketFrame {
     public BinaryWebSocketFrame copy() {
         return new BinaryWebSocketFrame(isFinalFragment(), rsv(), data().copy());
     }
+
+    @Override
+    public BinaryWebSocketFrame retain() {
+        super.retain();
+        return this;
+    }
+
+    @Override
+    public BinaryWebSocketFrame retain(int increment) {
+        super.retain(increment);
+        return this;
+    }
 }

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/CloseWebSocketFrame.java

@@ -143,4 +143,16 @@ public class CloseWebSocketFrame extends WebSocketFrame {
     public CloseWebSocketFrame copy() {
         return new CloseWebSocketFrame(isFinalFragment(), rsv(), data().copy());
     }
+
+    @Override
+    public CloseWebSocketFrame retain() {
+        super.retain();
+        return this;
+    }
+
+    @Override
+    public CloseWebSocketFrame retain(int increment) {
+        super.retain(increment);
+        return this;
+    }
 }

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/ContinuationWebSocketFrame.java

@@ -124,4 +124,15 @@ public class ContinuationWebSocketFrame extends WebSocketFrame {
         return new ContinuationWebSocketFrame(isFinalFragment(), rsv(), data().copy(), aggregatedText());
     }
 
+    @Override
+    public ContinuationWebSocketFrame retain() {
+        super.retain();
+        return this;
+    }
+
+    @Override
+    public ContinuationWebSocketFrame retain(int increment) {
+        super.retain(increment);
+        return this;
+    }
 }

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/PingWebSocketFrame.java

@@ -58,4 +58,16 @@ public class PingWebSocketFrame extends WebSocketFrame {
     public PingWebSocketFrame copy() {
         return new PingWebSocketFrame(isFinalFragment(), rsv(), data().copy());
     }
+
+    @Override
+    public PingWebSocketFrame retain() {
+        super.retain();
+        return this;
+    }
+
+    @Override
+    public PingWebSocketFrame retain(int increment) {
+        super.retain(increment);
+        return this;
+    }
 }

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/PongWebSocketFrame.java

@@ -59,4 +59,15 @@ public class PongWebSocketFrame extends WebSocketFrame {
         return new PongWebSocketFrame(isFinalFragment(), rsv(), data().copy());
     }
 
+    @Override
+    public PongWebSocketFrame retain() {
+        super.retain();
+        return this;
+    }
+
+    @Override
+    public PongWebSocketFrame retain(int increment) {
+        super.retain(increment);
+        return this;
+    }
 }

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/TextWebSocketFrame.java

@@ -98,4 +98,16 @@ public class TextWebSocketFrame extends WebSocketFrame {
     public TextWebSocketFrame copy() {
         return new TextWebSocketFrame(isFinalFragment(), rsv(), data().copy());
     }
+
+    @Override
+    public TextWebSocketFrame retain() {
+        super.retain();
+        return this;
+    }
+
+    @Override
+    public TextWebSocketFrame retain(int increment) {
+        super.retain(increment);
+        return this;
+    }
 }

codec-http/src/main/java/io/netty/handler/codec/http/websocketx/WebSocketFrame.java

@@ -67,4 +67,15 @@ public abstract class WebSocketFrame extends DefaultByteBufHolder {
         return getClass().getSimpleName() + "(data: " + data().toString() + ')';
     }
 
+    @Override
+    public WebSocketFrame retain() {
+        super.retain();
+        return this;
+    }
+
+    @Override
+    public WebSocketFrame retain(int increment) {
+        super.retain(increment);
+        return this;
+    }
 }