Update HTTP/2 ALTSVC wireformat from draft-04 to draft-06.

net/spdy/spdy_protocol.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.
 
 // This file contains some protocol structures for use with SPDY 2 and 3
 // The SPDY 2 spec can be found at:
 // http://dev.chromium.org/spdy/spdy-protocol/spdy-protocol-draft2
 // The SPDY 3 spec can be found at:
 // http://dev.chromium.org/spdy/spdy-protocol/spdy-protocol-draft3
 
@@ skipping 943 matching lines @@
   void Visit(SpdyFrameVisitor* visitor) const override;
 
   bool end_headers() const { return end_headers_; }
   void set_end_headers(bool end_headers) {end_headers_ = end_headers;}
 
  private:
   bool end_headers_;
   DISALLOW_COPY_AND_ASSIGN(SpdyContinuationIR);
 };
 
+// TODO(bnc): Add probability.
+// TODO(bnc): Separate (protocol, port, host, max_age, probability) tuple into
+// struct, have a vector of that struct.  A single HTTP/1.1 header field or
+// HTTP/2 or QUIC frame can define multiple such tuples.
 class NET_EXPORT_PRIVATE SpdyAltSvcIR : public SpdyFrameWithStreamIdIR {
  public:
   explicit SpdyAltSvcIR(SpdyStreamId stream_id);
 
   uint32 max_age() const { return max_age_; }
   uint16 port() const { return port_; }
   SpdyProtocolId protocol_id() const {
     return protocol_id_;
   }
   std::string host() const { return host_; }
@@ skipping 117 matching lines @@
   SpdyFrameVisitor() {}
   virtual ~SpdyFrameVisitor() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SpdyFrameVisitor);
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_SPDY_PROTOCOL_H_