Rewrite component update service in terms of components/update_client.

The goal of this change is to re-implement the component updater by
reusing the common code in components/update_client while keeping
the its public interface the same as before, in order to minimize
changes in its existing clients.

BUG=450337

Review URL: https://codereview.chromium.org/1133443002

Cr-Commit-Position: refs/heads/master@{#331412}

1 files changed, 42 insertions, 0 deletions

diff --git a/components/component_updater/timer.h b/components/component_updater/timer.h
new file mode 100644
index 0000000..8b72899
--- /dev/null
+++ b/components/component_updater/timer.h
@@ -0,0 +1,42 @@
+// Copyright 2015 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 COMPONENTS_COMPONENT_UPDATER_TIMER_H_
+#define COMPONENTS_COMPONENT_UPDATER_TIMER_H_
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/threading/thread_checker.h"
+#include "base/time/time.h"
+#include "base/timer/timer.h"
+
+namespace component_updater {
+
+class Timer {
+ public:
+  Timer();
+  ~Timer();
+
+  void Start(base::TimeDelta initial_delay,
+             base::TimeDelta delay,
+             const base::Closure& user_task);
+
+  void Stop();
+
+ private:
+  void OnDelay();
+
+  base::ThreadChecker thread_checker_;
+
+  base::Timer timer_;
+
+  base::TimeDelta delay_;
+  base::Closure user_task_;
+
+  DISALLOW_COPY_AND_ASSIGN(Timer);
+};
+
+}  // namespace component_updater
+
+#endif  // COMPONENTS_COMPONENT_UPDATER_TIMER_H_