Modify MainThreadWebSocketChannel to use enumeration for denotating its current state

Source/modules/websockets/MainThreadWebSocketChannel.h

Index: Source/modules/websockets/MainThreadWebSocketChannel.h
diff --git a/Source/modules/websockets/MainThreadWebSocketChannel.h b/Source/modules/websockets/MainThreadWebSocketChannel.h
index 8e4ac55edf23182c8c6ccd2166a8597cbcbaa233..1cc1aea6770e5bf6c4c2d27461840175bfa0df6d 100644
--- a/Source/modules/websockets/MainThreadWebSocketChannel.h
+++ b/Source/modules/websockets/MainThreadWebSocketChannel.h
@@ -173,6 +173,12 @@ private:
         BlobLoaderFailed
     };
 
+    enum ChannelState {
+        ChannelIdle,
+        ChannelClosing,
+        ChannelClosed
+    };
+
     Document* m_document;
     WebSocketChannelClient* m_client;
     OwnPtr<WebSocketHandshake> m_handshake;
@@ -181,11 +187,10 @@ private:
 
     Timer<MainThreadWebSocketChannel> m_resumeTimer;
     bool m_suspended;
-    bool m_closing;
     bool m_didFailOfClientAlreadyRun;
     bool m_receivedClosingHandshake;
     Timer<MainThreadWebSocketChannel> m_closingTimer;
-    bool m_closed;
+    ChannelState m_state;
     bool m_shouldDiscardReceivedData;
     unsigned long m_unhandledBufferedAmount;