Server push cancellation: add PushPromiseHelper which reflects information on the push promise.

net/quic/core/quic_client_session_base.h

 // Copyright 2014 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_QUIC_CLIENT_SESSION_BASE_H_
 #define NET_QUIC_QUIC_CLIENT_SESSION_BASE_H_
 
 #include <string>
 
 #include "base/macros.h"
@@ skipping 47 matching lines @@
 
   // Called by |QuicSpdyClientStream| on receipt of response headers,
   // needed to detect promised server push streams, as part of
   // client-request to push-stream rendezvous.
   void OnInitialHeadersComplete(QuicStreamId stream_id,
                                 const SpdyHeaderBlock& response_headers);
 
   // Called by |QuicSpdyClientStream| on receipt of PUSH_PROMISE, does
   // some session level validation and creates the
   // |QuicClientPromisedInfo| inserting into maps by (promised) id and
-  // url.
-  virtual void HandlePromised(QuicStreamId associated_id,
+  // url. Returns true if a new push promise is accepted. Reset the promised and
+  // returns false otherwiese.
+  virtual bool HandlePromised(QuicStreamId associated_id,
                               QuicStreamId promised_id,
                               const SpdyHeaderBlock& headers);
 
   // For cross-origin server push, this should verify the server is
   // authoritative per [RFC2818], Section 3.  Roughly, subjectAltName
   // std::list in the certificate should contain a matching DNS name, or IP
   // address.  |hostname| is derived from the ":authority" header field of
   // the PUSH_PROMISE frame, port if present there will be dropped.
   virtual bool IsAuthorized(const std::string& hostname) = 0;
 
@@ skipping 48 matching lines @@
   QuicClientPushPromiseIndex* push_promise_index_;
   QuicPromisedByIdMap promised_by_id_;
   QuicStreamId largest_promised_stream_id_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicClientSessionBase);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_CLIENT_SESSION_BASE_H_