Remove QuicChromiumClientStream::Delegate in favor of async methods.

net/quic/chromium/quic_chromium_client_stream.h

Index: net/quic/chromium/quic_chromium_client_stream.h
diff --git a/net/quic/chromium/quic_chromium_client_stream.h b/net/quic/chromium/quic_chromium_client_stream.h
index e95d47840629d81a4c5940db3c8f7877a47ce6a0..a29e118a670198e2ed850b1282c047661a4c6e3e 100644
--- a/net/quic/chromium/quic_chromium_client_stream.h
+++ b/net/quic/chromium/quic_chromium_client_stream.h
@@ -32,26 +32,6 @@ class QuicClientSessionBase;
 // are owned by the QuicClientSession which created them.
 class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
  public:
-  // TODO(rch): Remove this class completely in favor of async methods
-  // on the Handle.
-  // Delegate handles protocol specific behavior of a quic stream.
-  class NET_EXPORT_PRIVATE Delegate {
-   public:
-    Delegate() {}
-
-    // Called when the stream is closed by the peer.
-    virtual void OnClose() = 0;
-
-    // Called when the stream is closed because of an error.
-    virtual void OnError(int error) = 0;
-
-   protected:
-    virtual ~Delegate() {}
-
-   private:
-    DISALLOW_COPY_AND_ASSIGN(Delegate);
-  };
-
   // Wrapper for interacting with the session in a restricted fashion.
   class NET_EXPORT_PRIVATE Handle {
    public:
@@ -90,10 +70,10 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
     // Writes |header_block| to the peer. Closes the write side if |fin| is
     // true. If non-null, |ack_notifier_delegate| will be notified when the
     // headers are ACK'd by the peer.
-    size_t WriteHeaders(SpdyHeaderBlock header_block,
-                        bool fin,
-                        QuicReferenceCountedPointer<QuicAckListenerInterface>
-                            ack_notifier_delegate);
+    int WriteHeaders(SpdyHeaderBlock header_block,

[xunjieli, 2017/05/31 00:25:22]

Could you add a comment here mentioning that the return value is a net error
code?

[Ryan Hamilton, 2017/05/31 02:49:56]

Done.

+                     bool fin,
+                     QuicReferenceCountedPointer<QuicAckListenerInterface>
+                         ack_notifier_delegate);
 
     // Writes |data| to the peer. Closes the write side if |fin| is true.
     // If the data could not be written immediately, returns ERR_IO_PENDING
@@ -126,10 +106,6 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
     // Sends a RST_STREAM frame to the peer and closes the streams.
     void Reset(QuicRstStreamErrorCode error_code);
 
-    // Clears |delegate_| from this Handle, but does not disconnect the Handle
-    // from |stream_|.
-    void ClearDelegate();
-
     QuicStreamId id() const;
     QuicErrorCode connection_error() const;
     QuicRstStreamErrorCode stream_error() const;
@@ -148,14 +124,11 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
     SpdyPriority priority() const;
     bool can_migrate();
 
-    Delegate* GetDelegate();
-
    private:
     friend class QuicChromiumClientStream;
 
-    // Constucts a new Handle for |stream| with |delegate| set to receive
-    // up calls on various events.
-    Handle(QuicChromiumClientStream* stream, Delegate* delegate);
+    // Constucts a new Handle for |stream|.
+    explicit Handle(QuicChromiumClientStream* stream);
 
     // Methods invoked by the stream.
     void OnInitialHeadersAvailable();
@@ -165,11 +138,22 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
     void OnClose();
     void OnError(int error);
 
+    // Invokes async IO callbacks because of |error|.
+    void InvokeCallbacksOnError(int error);
+
     // Saves various fields from the stream before the stream goes away.
     void SaveState();
 
+    void SetCallback(CompletionCallback new_callback,
+                     CompletionCallback* callback);
+
+    void ResetAndRun(CompletionCallback* callback, int rv);
+
+    int HandleIOComplete(int rv);
+
     QuicChromiumClientStream* stream_;  // Unowned.
-    Delegate* delegate_;                // Owns this.
+
+    bool may_invoke_callbacks_;  // True when callbacks may be invoked.
 
     // Callback to be invoked when ReadHeaders completes asynchronously.
     CompletionCallback read_headers_callback_;
@@ -196,6 +180,10 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
     size_t num_bytes_consumed_;
     SpdyPriority priority_;
 
+    int net_error_;
+
+    base::WeakPtrFactory<Handle> weak_factory_;
+
     DISALLOW_COPY_AND_ASSIGN(Handle);
   };
 
@@ -238,10 +226,8 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
                         const std::vector<int>& lengths,
                         bool fin);
 
-  // Creates a new Handle for this stream and sets |delegate| on the handle.
-  // Must only be called once.
-  std::unique_ptr<QuicChromiumClientStream::Handle> CreateHandle(
-      QuicChromiumClientStream::Delegate* delegate);
+  // Creates a new Handle for this stream. Must only be called once.
+  std::unique_ptr<QuicChromiumClientStream::Handle> CreateHandle();
 
   // Clears |handle_| from this stream.
   void ClearHandle();
@@ -290,7 +276,7 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
   // Set to false if this stream to not be migrated during connection migration.
   bool can_migrate_;
 
-  // Stores the initial header if they arrive before the delegate.
+  // Stores the initial header if they arrive before the handle.
   SpdyHeaderBlock initial_headers_;
   // Length of the HEADERS frame containing initial headers.
   size_t initial_headers_frame_len_;