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

components/cronet/ios/cronet_bidirectional_stream.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 COMPONENTS_CRONET_IOS_CRONET_BIDIRECTIONAL_STREAM_H_
 #define COMPONENTS_CRONET_IOS_CRONET_BIDIRECTIONAL_STREAM_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 99 matching lines @@
     // Waiting for WriteData() to be called.
     WAITING_FOR_WRITE,
     // Writing to the remote, callback will be invoked when done.
     WRITING,
     // There is no more data to write and stream is half-closed by the local
     // side.
     WRITING_DONE,
   };
 
   // net::BidirectionalStream::Delegate implementations:
-  void OnStreamReady() override;
+  void OnStreamReady(bool request_headers_sent) override;
   void OnHeadersReceived(const net::SpdyHeaderBlock& response_headers) override;
   void OnDataRead(int bytes_read) override;
   void OnDataSent() override;
   void OnTrailersReceived(const net::SpdyHeaderBlock& trailers) override;
   void OnFailed(int error) override;
   // Helper method to derive OnSucceeded.
   void MaybeOnSucceded();
 
   void StartOnNetworkThread(
       std::unique_ptr<net::BidirectionalStreamRequestInfo> request_info);
@@ skipping 27 matching lines @@
   scoped_refptr<net::WrappedIOBuffer> write_buffer_;
   std::unique_ptr<net::BidirectionalStream> bidi_stream_;
   Delegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(CronetBidirectionalStream);
 };
 
 }  // namespace cronet
 
 #endif  // COMPONENTS_CRONET_IOS_CRONET_BIDIRECTIONAL_STREAM_H_