[GCM] Add more UMA to GCM

google_apis/gcm/gcm_client.h

 // Copyright 2013 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 GOOGLE_APIS_GCM_GCM_CLIENT_H_
 #define GOOGLE_APIS_GCM_GCM_CLIENT_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 49 matching lines @@
   // Message to be delivered to the other party.
   struct GCM_EXPORT OutgoingMessage {
     OutgoingMessage();
     ~OutgoingMessage();
 
     // Message ID.
     std::string id;
     // In seconds.
     int time_to_live;
     MessageData data;
+
+    static const int kMaximumTTL = 4 * 7 * 24 * 60 * 60;  // 4 weeks.
   };
 
   // Message being received from the other party.
   struct GCM_EXPORT IncomingMessage {
     IncomingMessage();
     ~IncomingMessage();
 
     MessageData data;
     std::string collapse_key;
     std::string sender_id;
@@ skipping 141 matching lines @@
   // Clear all recorded GCM activity logs.
   virtual void ClearActivityLogs() = 0;
 
   // Gets internal states and statistics.
   virtual GCMStatistics GetStatistics() const = 0;
 };
 
 }  // namespace gcm
 
 #endif  // GOOGLE_APIS_GCM_GCM_CLIENT_H_