Add the basic code skeleton for system info event router

chrome/browser/extensions/mock_system_info_watcher.h

Index: chrome/browser/extensions/mock_system_info_watcher.h
diff --git a/chrome/browser/extensions/mock_system_info_watcher.h b/chrome/browser/extensions/mock_system_info_watcher.h
new file mode 100644
index 0000000000000000000000000000000000000000..440da5354fdf24a1e21d1443f217dc4269a35be9
--- /dev/null
+++ b/chrome/browser/extensions/mock_system_info_watcher.h
@@ -0,0 +1,33 @@
+// Copyright (c) 2012 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 CHROME_BROWSER_EXTENSIONS_MOCK_SYSTEM_INFO_WATCHER_H_
+#define CHROME_BROWSER_EXTENSIONS_MOCK_SYSTEM_INFO_WATCHER_H_
+
+#include "chrome/browser/extensions/system_info_watcher.h"
+
+#include "base/timer.h"
+
+namespace extensions {
+
+class MockSystemInfoWatcher : public SystemInfoWatcher {
+ public:
+  MockSystemInfoWatcher();
+  virtual ~MockSystemInfoWatcher();
+
+ private:
+  // SystemInfoWatcher implementation.
+  virtual bool PlatformStartWatching(const std::string& event_name) OVERRIDE;
+  virtual bool PlatformStopWatching(const std::string& event_name) OVERRIDE;
+
+  // Called when the timer gets expired. It is used to emulate the random
+  // system event.
+  void OnTimeoutEvent();
+
+  base::RepeatingTimer<MockSystemInfoWatcher> timer_;
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_MOCK_SYSTEM_INFO_WATCHER_H_
+