[Cronet]Make delaying sending request headers explicit in bidirectional stream

net/quic/bidirectional_stream_quic_impl.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_QUIC_BIDIRECTIONAL_STREAM_QUIC_IMPL_H_
 #define NET_QUIC_BIDIRECTIONAL_STREAM_QUIC_IMPL_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 21 matching lines @@
       public QuicChromiumClientSession::Observer {
  public:
   explicit BidirectionalStreamQuicImpl(
       const base::WeakPtr<QuicChromiumClientSession>& session);
 
   ~BidirectionalStreamQuicImpl() override;
 
   // BidirectionalStreamImpl implementation:
   void Start(const BidirectionalStreamRequestInfo* request_info,
              const BoundNetLog& net_log,
-             bool disable_auto_flush,
+             bool send_request_headers_automatically,
              BidirectionalStreamImpl::Delegate* delegate,
              std::unique_ptr<base::Timer> timer) override;
+  void SendRequestHeaders() override;
   int ReadData(IOBuffer* buffer, int buffer_len) override;
   void SendData(const scoped_refptr<IOBuffer>& data,
                 int length,
                 bool end_stream) override;
   void SendvData(const std::vector<scoped_refptr<IOBuffer>>& buffers,
                  const std::vector<int>& lengths,
                  bool end_stream) override;
   void Cancel() override;
   NextProto GetProtocol() const override;
   int64_t GetTotalReceivedBytes() const override;
   int64_t GetTotalSentBytes() const override;
 
  private:
   // QuicChromiumClientStream::Delegate implementation:
   void OnHeadersAvailable(const SpdyHeaderBlock& headers,
                           size_t frame_len) override;
   void OnDataAvailable() override;
   void OnClose(QuicErrorCode error) override;
   void OnError(int error) override;
   bool HasSendHeadersComplete() override;
 
   // QuicChromiumClientSession::Observer implementation:
   void OnCryptoHandshakeConfirmed() override;
   void OnSessionClosed(int error, bool port_migration_detected) override;
 
   void OnStreamReady(int rv);
   void OnSendDataComplete(int rv);
   void OnReadDataComplete(int rv);
 
-  // Helper method to send request headers.
-  void SendRequestHeaders();
   // Notifies the delegate of an error.
   void NotifyError(int error);
   // Resets the stream and ensures that |delegate_| won't be called back.
   void ResetStream();
 
   base::WeakPtr<QuicChromiumClientSession> session_;
   bool was_handshake_confirmed_;  // True if the crypto handshake succeeded.
   QuicChromiumClientSession::StreamRequest stream_request_;
   QuicChromiumClientStream* stream_;  // Non-owning.
 
@@ skipping 18 matching lines @@
   // bytes received over the network for |stream_| while it was open.
   int64_t closed_stream_received_bytes_;
   // After |stream_| has been closed, this keeps track of the total number of
   // bytes sent over the network for |stream_| while it was open.
   int64_t closed_stream_sent_bytes_;
   // Indicates whether initial headers have been sent.
   bool has_sent_headers_;
   // Indicates whether initial headers have been received.
   bool has_received_headers_;
 
-  bool disable_auto_flush_;
+  // Whether to automatically send request headers when stream is negotiated.
+  // If false, headers will not be sent until SendRequestHeaders() is called or
+  // until next SendData/SendvData, during which QUIC will try to combine header
+  // frame with data frame in the same packet if possible.
+  bool send_request_headers_automatically_;
 
   base::WeakPtrFactory<BidirectionalStreamQuicImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BidirectionalStreamQuicImpl);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_BIDIRECTIONAL_STREAM_QUIC_IMPL_H_