[Offline pages] Resetting offline page metadata store to handle LOAD/INIT failures

components/offline_pages/offline_page_metadata_store_sql.h

Index: components/offline_pages/offline_page_metadata_store_sql.h
diff --git a/components/offline_pages/offline_page_metadata_store_sql.h b/components/offline_pages/offline_page_metadata_store_sql.h
index c26cae8fb3e6653ee5f3224d2cda2cc55115607c..1adb9f8e884b3b1697bfb32c1a26994f1a2116ff 100644
--- a/components/offline_pages/offline_page_metadata_store_sql.h
+++ b/components/offline_pages/offline_page_metadata_store_sql.h
@@ -58,6 +58,7 @@ class OfflinePageMetadataStoreSQL : public OfflinePageMetadataStore {
   ~OfflinePageMetadataStoreSQL() override;
 
   // Implementation methods.
+  void Initialize(const InitializeCallback& callback) override;
   void GetOfflinePages(const LoadCallback& callback) override;
   void AddOfflinePage(const OfflinePageItem& offline_page,
                       const AddCallback& callback) override;
@@ -65,19 +66,16 @@ class OfflinePageMetadataStoreSQL : public OfflinePageMetadataStore {
                           const UpdateCallback& callback) override;
   void RemoveOfflinePages(const std::vector<int64_t>& offline_ids,
                           const UpdateCallback& callback) override;
-  void Reset(const ResetCallback& callback) override;
+  void Reset(const InitializeCallback& callback) override;
   StoreState state() const override;
 
   // Helper function used to force incorrect state for testing purposes.
   void SetStateForTesting(StoreState state, bool reset_db);
 
  private:
-  // Used to initialize DB connection.
-  void OpenConnection();
-  void OnOpenConnectionDone(StoreState state);
-
-  // Used to reset DB connection.
-  void OnResetDone(const ResetCallback& callback, StoreState state);
+  // Used to conclude opening/resetting DB connection.
+  void OnOpenConnectionDone(const InitializeCallback& callback,
+                            StoreState state);
 
   // Helper function that checks whether a valid DB connection is present.
   // Returns true if valid connection is present, otherwise it returns false and