components: Introduce AlarmTimer class and use it for GCM heartbeat

google_apis/gcm/engine/mcs_client.cc

Index: google_apis/gcm/engine/mcs_client.cc
diff --git a/google_apis/gcm/engine/mcs_client.cc b/google_apis/gcm/engine/mcs_client.cc
index ec156b786f8e6bbeecf574e9dc25d6e734cd1a12..31b283232f5cffb17c4b48b71ab97fe4ca932b28 100644
--- a/google_apis/gcm/engine/mcs_client.cc
+++ b/google_apis/gcm/engine/mcs_client.cc
@@ -7,11 +7,13 @@
 #include <set>
 
 #include "base/basictypes.h"
+#include "base/bind.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/time/clock.h"
 #include "base/time/time.h"
+#include "base/timer/timer.h"
 #include "google_apis/gcm/base/mcs_util.h"
 #include "google_apis/gcm/base/socket_stream.h"
 #include "google_apis/gcm/engine/connection_factory.h"
@@ -157,7 +159,8 @@ MCSClient::MCSClient(const std::string& version_string,
                      base::Clock* clock,
                      ConnectionFactory* connection_factory,
                      GCMStore* gcm_store,
-                     GCMStatsRecorder* recorder)
+                     GCMStatsRecorder* recorder,
+                     scoped_ptr<base::Timer> timer)
     : version_string_(version_string),
       clock_(clock),
       state_(UNINITIALIZED),
@@ -170,6 +173,7 @@ MCSClient::MCSClient(const std::string& version_string,
       stream_id_out_(0),
       stream_id_in_(0),
       gcm_store_(gcm_store),
+      heartbeat_manager_(timer.Pass()),
       recorder_(recorder),
       weak_ptr_factory_(this) {
 }