Tether: Break helper TimerFactory out of BleConnectionManager and HostScanCache.

chromeos/components/tether/timer_factory.h

+// Copyright 2017 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 CHROMEOS_COMPONENTS_TETHER_TIMER_FACTORY_H_
+#define CHROMEOS_COMPONENTS_TETHER_TIMER_FACTORY_H_
+
+#include <memory>
+
+#include "base/macros.h"
+#include "base/memory/ptr_util.h"
+#include "base/timer/timer.h"
+
+namespace chromeos {
+
+namespace tether {
+
+// Serves as a simple Timer creator, injected into classes that use Timers.
+// Is intended to be overriden during testing in order to stub or mock the
+// Timers used by the object under test.
+class TimerFactory {
+ public:
+  virtual ~TimerFactory();
+
+  virtual std::unique_ptr<base::Timer> CreateOneShotTimer();
+};
+
+}  // namespace tether
+
+}  // namespace chromeos
+
+#endif  // CHROMEOS_COMPONENTS_TETHER_TIMER_FACTORY_H_