[Offline Pages] Create a event/activity logger

components/offline_pages/offline_page_model_event_logger.h

+// Copyright 2016 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_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_EVENT_LOGGER_H_
+#define COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_EVENT_LOGGER_H_
+
+#include "components/offline_pages/offline_event_logger.h"
+
+namespace offline_pages {
+
+class OfflinePageModelEventLogger : public OfflineEventLogger {
+ public:
+  // Records that a page has been saved for |name_space| with |url| and |id|.
+  void RecordPageSaved(const std::string& name_space,
+                       const std::string& url,
+                       const std::string& id);

[fgorski, 2016/06/23 16:34:07]

please document which ID it is.
If it is part of the client id, please consider moving it next to namespace. if
offline ID it can stay

[chili, 2016/06/24 02:45:52]

Done.

+
+  // Records that a page with |id| has been deleted.

[fgorski, 2016/06/23 16:34:07]

same: document ID please.

[chili, 2016/06/24 02:45:52]

Done.

+  void RecordPageDeleted(const std::string& id);
+
+  // Records that the offline store has been cleared.
+  void RecordStoreCleared();
+
+  // Records that there was an error when clearing the offline store.
+  void RecordStoreClearError();
+
+  // Records that there was an error when reloading the offline store.
+  void RecordStoreReloadError();
+};
+
+}  // namespace offline_pages
+
+#endif  // COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_EVENT_LOGGER_H_