[HttpStreamParser]: Flush buffers as soon as request is sent.

net/http/http_stream_parser.h

 // Copyright (c) 2012 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_HTTP_HTTP_STREAM_PARSER_H_
 #define NET_HTTP_HTTP_STREAM_PARSER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 117 matching lines @@
   // operations and don't necessarily mean that FOO is complete.
   enum State {
     // STATE_NONE indicates that this is waiting on an external call before
     // continuing.
     STATE_NONE,
     STATE_SEND_HEADERS,
     STATE_SEND_HEADERS_COMPLETE,
     STATE_SEND_BODY,
     STATE_SEND_BODY_COMPLETE,
     STATE_SEND_REQUEST_READ_BODY_COMPLETE,
+    STATE_SEND_REQUEST_COMPLETE,
     STATE_READ_HEADERS,
     STATE_READ_HEADERS_COMPLETE,
     STATE_READ_BODY,
     STATE_READ_BODY_COMPLETE,
     STATE_DONE
   };
 
   // The number of bytes by which the header buffer is grown when it reaches
   // capacity.
   static const int kHeaderBufInitialSize = 4 * 1024;  // 4K
@@ skipping 12 matching lines @@
 
   // Try to make progress sending/receiving the request/response.
   int DoLoop(int result);
 
   // The implementations of each state of the state machine.
   int DoSendHeaders();
   int DoSendHeadersComplete(int result);
   int DoSendBody();
   int DoSendBodyComplete(int result);
   int DoSendRequestReadBodyComplete(int result);
+  int DoSendRequestComplete(int result);
   int DoReadHeaders();
   int DoReadHeadersComplete(int result);
   int DoReadBody();
   int DoReadBodyComplete(int result);
 
   // This handles most of the logic for DoReadHeadersComplete.
   int HandleReadHeaderResult(int result);
 
   // Examines |read_buf_| to find the start and end of the headers. If they are
   // found, parse them with DoParseResponseHeaders().  Return the offset for
   // the end of the headers, or -1 if the complete headers were not found, or
   // with a net::Error if we encountered an error during parsing.
   int FindAndParseResponseHeaders();
 
   // Parse the headers into response_.  Returns OK on success or a net::Error on
   // failure.
   int ParseResponseHeaders(int end_of_header_offset);
 
   // Examine the parsed headers to try to determine the response body size.
   void CalculateResponseBodySize();
 
   // Uploads statistics about status line compliance with RFC 7230.
   void ValidateStatusLine(const std::string& status_line);
 
+  // Check if buffers used to send the request are empty.
+  bool SendRequestBuffersEmpty();
+
   // Next state of the request, when the current one completes.
   State io_state_;
 
   // The request to send.
   const HttpRequestInfo* request_;
 
   // The request header data.  May include a merged request body.
   scoped_refptr<DrainableIOBuffer> request_headers_;
 
   // Size of just the request headers.  May be less than the length of
@@ skipping 72 matching lines @@
   int upload_error_;
 
   base::WeakPtrFactory<HttpStreamParser> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HttpStreamParser);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_STREAM_PARSER_H_