Move the async write handling from QuicChromiumClientStream to the Handle

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 14901d8edcfdfbbc67c6c7b1fd53a7a1f3410581..82841a470fb16953b732758920bb2e14bfaae578 100644
--- a/net/quic/chromium/quic_chromium_client_stream.h
+++ b/net/quic/chromium/quic_chromium_client_stream.h
@@ -157,6 +157,7 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
     void OnTrailingHeadersAvailable(const SpdyHeaderBlock& headers,
                                     size_t frame_len);
     void OnDataAvailable();
+    void OnCanWrite();
     void OnClose();
     void OnError(int error);
 
@@ -166,13 +167,19 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
     QuicChromiumClientStream* stream_;  // Unowned.
     Delegate* delegate_;                // Owns this.
 
+    // Callback to be invoked when ReadHeaders completes asynchronously.
     CompletionCallback read_headers_callback_;
     SpdyHeaderBlock* read_headers_buffer_;
 
+    // Callback to be invoked when ReadBody completes asynchronously.
     CompletionCallback read_body_callback_;
     IOBuffer* read_body_buffer_;
     int read_body_buffer_len_;
 
+    // Callback to be invoked when WriteStreamData or WritevStreamData completes
+    // asynchronously.
+    CompletionCallback write_callback_;
+
     QuicStreamId id_;
     QuicErrorCode connection_error_;
     QuicRstStreamErrorCode stream_error_;
@@ -217,15 +224,15 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
   // of client-side streams should be able to set the priority.
   using QuicSpdyStream::SetPriority;
 
-  int WriteStreamData(QuicStringPiece data,
-                      bool fin,
-                      const CompletionCallback& callback);
+  // Writes |data| to the peer, loses the write side if |fin| is true and

[xunjieli, 2017/05/15 15:48:36]

minor nit: Maybe break the sentence after "and" or remove "Returns false
otherwise." 

e.g. 

Writes |data| to the peer and closes the write side if |fin| is true.
Returns true if the data have been fully written.

[xunjieli, 2017/05/15 15:48:36]

nit: loses/closes

[Ryan Hamilton, 2017/05/20 22:24:54]

Done.

[Ryan Hamilton, 2017/05/20 22:24:54]

Done.

+  // returns true if the data could actually be written. Returns false

[xunjieli, 2017/05/15 15:48:37]

nit: "could actually be written" isn't as precise. Maybe consider rephrasing?

maybe s/could actually be written/have been fully written?

Could you also mention that if the data cannot be fully written synchronously,
OnCanWrite() will be invoked later?

[Ryan Hamilton, 2017/05/20 22:24:54]

Done.

+  // otherwise.
+  bool WriteStreamData(QuicStringPiece data, bool fin);
   // Same as WriteStreamData except it writes data from a vector of IOBuffers,
   // with the length of each buffer at the corresponding index in |lengths|.
-  int WritevStreamData(const std::vector<scoped_refptr<IOBuffer>>& buffers,
-                       const std::vector<int>& lengths,
-                       bool fin,
-                       const CompletionCallback& callback);
+  bool WritevStreamData(const std::vector<scoped_refptr<IOBuffer>>& buffers,
+                        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.
@@ -274,10 +281,6 @@ class NET_EXPORT_PRIVATE QuicChromiumClientStream : public QuicSpdyStream {
   // True when initial headers have been sent.
   bool initial_headers_sent_;
 
-  // Callback to be invoked when WriteStreamData or WritevStreamData completes
-  // asynchronously.
-  CompletionCallback write_callback_;
-
   QuicClientSessionBase* session_;
 
   // Set to false if this stream to not be migrated during connection migration.