[GCM] Add heartbeat manager and reconnection logic due to heartbeat failure

google_apis/gcm/engine/mcs_client.h

Index: google_apis/gcm/engine/mcs_client.h
diff --git a/google_apis/gcm/engine/mcs_client.h b/google_apis/gcm/engine/mcs_client.h
index 4de62cb127e218121e8676f2a8d7425945b2b4a0..3137c9f50e91e71e099b2a570162fd4500363d78 100644
--- a/google_apis/gcm/engine/mcs_client.h
+++ b/google_apis/gcm/engine/mcs_client.h
@@ -13,10 +13,10 @@
 #include "base/files/file_path.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/weak_ptr.h"
-#include "base/timer/timer.h"
 #include "google_apis/gcm/base/gcm_export.h"
 #include "google_apis/gcm/base/mcs_message.h"
 #include "google_apis/gcm/engine/connection_handler.h"
+#include "google_apis/gcm/engine/heartbeat_manager.h"
 #include "google_apis/gcm/engine/rmq_store.h"
 
 namespace google {
@@ -155,6 +155,9 @@ class GCM_EXPORT MCSClient {
   // Virtual for testing.
   virtual PersistentId GetNextPersistentId();
 
+  // Helper for the heartbeat manager to signal a connection reset.
+  void OnConnectionResetByHeartbeat();
+
   // Client state.
   State state_;
 
@@ -212,11 +215,8 @@ class GCM_EXPORT MCSClient {
   // The reliable message queue persistent store.
   RMQStore rmq_store_;
 
-  // ----- Heartbeats -----
-  // The current heartbeat interval.
-  base::TimeDelta heartbeat_interval_;
-  // Timer for triggering heartbeats.
-  base::Timer heartbeat_timer_;
+  // Manager to handle triggering/detecting heartbeats.
+  HeartbeatManager heartbeat_manager_;
 
   // The task runner for blocking tasks (i.e. persisting RMQ state to disk).
   scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;