Remove unused return value from QuicAlarm::Delegate::OnAlarm. No behavior change, not protected.

net/quic/quic_client_promised_info.h

 // Copyright (c) 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_QUIC_CLIENT_PROMISED_INFO_H_
 #define NET_QUIC_QUIC_CLIENT_PROMISED_INFO_H_
 
 #include <sys/types.h>
 #include <string>
 
@@ skipping 65 matching lines @@
   const std::string url() const { return url_; }
 
  private:
   friend class test::QuicClientPromisedInfoPeer;
 
   class CleanupAlarm : public QuicAlarm::Delegate {
    public:
     explicit CleanupAlarm(QuicClientPromisedInfo* promised)
         : promised_(promised) {}
 
-    QuicTime OnAlarm() override;
+    void OnAlarm() override;
 
     QuicClientPromisedInfo* promised_;
   };
 
   void Reset(QuicRstStreamErrorCode error_code);
 
   QuicAsyncStatus FinalValidation();
 
   QuicClientSessionBase* session_;
   QuicConnectionHelperInterface* helper_;
   QuicStreamId id_;
   std::string url_;
   std::unique_ptr<SpdyHeaderBlock> request_headers_;
   std::unique_ptr<SpdyHeaderBlock> response_headers_;
   std::unique_ptr<SpdyHeaderBlock> client_request_headers_;
   QuicClientPushPromiseIndex::Delegate* client_request_delegate_;
 
   // The promise will commit suicide eventually if it is not claimed
   // by a GET first.
   std::unique_ptr<QuicAlarm> cleanup_alarm_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicClientPromisedInfo);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_CLIENT_PROMISED_INFO_H_