components: Introduce AlarmTimer class and use it for GCM heartbeat

google_apis/gcm/engine/heartbeat_manager.cc

Index: google_apis/gcm/engine/heartbeat_manager.cc
diff --git a/google_apis/gcm/engine/heartbeat_manager.cc b/google_apis/gcm/engine/heartbeat_manager.cc
index 5b5ae476a4b80be6ed896e98289d56fc0e771e48..9337b27a92f23e448f579a33d9a316345f1b8060 100644
--- a/google_apis/gcm/engine/heartbeat_manager.cc
+++ b/google_apis/gcm/engine/heartbeat_manager.cc
@@ -7,6 +7,12 @@
 #include "google_apis/gcm/protocol/mcs.pb.h"
 #include "net/base/network_change_notifier.h"
 
+#if defined(OS_CHROMEOS)
+#include "components/timer/alarm_timer.h"
+#else
+#include "base/timer/timer.h"
+#endif
+
 namespace gcm {
 
 namespace {
@@ -22,8 +28,14 @@ HeartbeatManager::HeartbeatManager()
     : waiting_for_ack_(false),
       heartbeat_interval_ms_(0),
       server_interval_ms_(0),
-      heartbeat_timer_(true  /* retain user task */,
-                       false  /* not repeating */),
+#if defined(OS_CHROMEOS)
+      heartbeat_timer_(make_scoped_ptr(

[Nicolas Zea, 2014/10/21 17:57:54]

do you need to call make_scoped_ptr here?

[Chirantan Ekbote, 2014/10/21 21:13:48]

I remember reading somewhere that you couldn't construct a scoped_ptr<parent>
with just a child* but I can't find it now and it looks like it actually works
just fine.  I ended up having to change this section anyway to deal with the
DEPS problem.

+          new timer::AlarmTimer(true  /* retain user task */,
+                                false  /* not repeating */)).Pass()),
+#else
+      heartbeat_timer_(new base::Timer(true  /* retain user task */,
+                                       false  /* not repeating */)),
+#endif
       weak_ptr_factory_(this) {}
 
 HeartbeatManager::~HeartbeatManager() {}
@@ -42,12 +54,12 @@ void HeartbeatManager::Start(
 }
 
 void HeartbeatManager::Stop() {
-  heartbeat_timer_.Stop();
+  heartbeat_timer_->Stop();
   waiting_for_ack_ = false;
 }
 
 void HeartbeatManager::OnHeartbeatAcked() {
-  if (!heartbeat_timer_.IsRunning())
+  if (!heartbeat_timer_->IsRunning())
     return;
 
   DCHECK(!send_heartbeat_callback_.is_null());
@@ -68,8 +80,8 @@ void HeartbeatManager::UpdateHeartbeatConfig(
 }
 
 base::TimeTicks HeartbeatManager::GetNextHeartbeatTime() const {
-  if (heartbeat_timer_.IsRunning())
-    return heartbeat_timer_.desired_run_time();
+  if (heartbeat_timer_->IsRunning())
+    return heartbeat_timer_->desired_run_time();
   else
     return base::TimeTicks();
 }
@@ -109,7 +121,7 @@ void HeartbeatManager::RestartTimer() {
     DVLOG(1) << "Resetting timer for ack with "
              << heartbeat_interval_ms_ << " ms interval.";
   }
-  heartbeat_timer_.Start(FROM_HERE,
+  heartbeat_timer_->Start(FROM_HERE,
                          base::TimeDelta::FromMilliseconds(
                              heartbeat_interval_ms_),
                          base::Bind(&HeartbeatManager::OnHeartbeatTriggered,