[GCM] Minimum change for periodic checkin

google_apis/gcm/engine/gcm_store.h

Index: google_apis/gcm/engine/gcm_store.h
diff --git a/google_apis/gcm/engine/gcm_store.h b/google_apis/gcm/engine/gcm_store.h
index 659fc7f9d1eaa2950a4732f9c5da87ac9b4b95af..ccf480bcda078c831f18abd28f63b1c7f3b1bb15 100644
--- a/google_apis/gcm/engine/gcm_store.h
+++ b/google_apis/gcm/engine/gcm_store.h
@@ -14,6 +14,7 @@
 #include "base/memory/linked_ptr.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/time/time.h"
 #include "google_apis/gcm/base/gcm_export.h"
 #include "google_apis/gcm/engine/registration_info.h"
 #include "google_apis/gcm/protocol/mcs.pb.h"
@@ -47,6 +48,7 @@ class GCM_EXPORT GCMStore {
     RegistrationInfoMap registrations;
     std::vector<std::string> incoming_messages;
     OutgoingMessageMap outgoing_messages;
+    base::Time last_checkin_time;
   };
 
   typedef std::vector<std::string> PersistentIdList;
@@ -101,6 +103,10 @@ class GCM_EXPORT GCMStore {
   virtual void RemoveOutgoingMessages(const PersistentIdList& persistent_ids,
                                       const UpdateCallback& callback) = 0;
 
+  // Sets last device's checkin time.
+  virtual void SetLastCheckinTime(const base::Time& last_checkin_time,
+                                  const UpdateCallback& callback) = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(GCMStore);
 };