[Offline pages] Detecting offline pages missing bookmarks

components/offline_pages/offline_page_model.h

Index: components/offline_pages/offline_page_model.h
diff --git a/components/offline_pages/offline_page_model.h b/components/offline_pages/offline_page_model.h
index 631d522ecc3ddf22193ef195f9f6c6266a17f7d5..aba944e3951343745411e38c728c63f619732e0f 100644
--- a/components/offline_pages/offline_page_model.h
+++ b/components/offline_pages/offline_page_model.h
@@ -195,11 +195,15 @@ class OfflinePageModel : public KeyedService,
   // not found.
   const OfflinePageItem* GetPageByOnlineURL(const GURL& online_url) const;
 
-  // Checks that all of the offline pages have corresponding offline copies.
-  // If a page is discovered to be missing an offline copy, its offline page
-  // metadata will be removed and |OfflinePageDeleted| will be sent to model
-  // observers.
-  void CheckForExternalFileDeletion();
+  // Checks for and fixes the following problems with offline pages metadata:
+  // * removes pages marked for deletion when |finalize_deletion| is set to
+  // true,
+  // * removes pages that don't have a corresponding bookmark mode in the
+  // bookmarks model,
+  // * removes pages that don't have the offline archive.
+  // Metadata checks run only when the bookmark model is loaded. If a metadata
+  // check is already in progress, the method returns.
+  void CheckMetadataConsistency(bool finalize_deletion);
 
   // Methods for testing only:
   OfflinePageMetadataStore* GetStoreForTesting();
@@ -213,6 +217,9 @@ class OfflinePageModel : public KeyedService,
   typedef ScopedVector<OfflinePageArchiver> PendingArchivers;
 
   // BaseBookmarkModelObserver:
+  void BookmarkModelLoaded(bookmarks::BookmarkModel* model,
+                           bool ids_reassigned) override;
+  void BookmarkModelBeingDeleted(bookmarks::BookmarkModel* model) override;
   void BookmarkModelChanged() override;
   void BookmarkNodeAdded(bookmarks::BookmarkModel* model,
                          const bookmarks::BookmarkNode* parent,
@@ -274,7 +281,13 @@ class OfflinePageModel : public KeyedService,
   void UndoPageDeletion(int64 bookmark_id);
   void OnUndoOfflinePageDone(const OfflinePageItem& offline_page, bool success);
 
-  // Callbacks for checking if offline pages are missing archive files.
+  // Callbacks and steps for checking offline page metadata consistency.
+  //
+  // Checks that all of the offline pages have corresponding offline copies.
+  // If a page is discovered to be missing an offline copy, its offline page
+  // metadata will be removed and |OfflinePageDeleted| will be sent to model
+  // observers.
+  void CheckForExternalFileDeletion(DeletePageResult);
   void OnFindPagesMissingArchiveFile(
       const std::vector<int64>* pages_missing_archive_file);
   void OnRemoveOfflinePagesMissingArchiveFileDone(
@@ -303,6 +316,9 @@ class OfflinePageModel : public KeyedService,
 
   bool is_loaded_;
 
+  // Whether a metadata check is going on right now.
+  bool metadata_check_in_progress_;
+
   // In memory copy of the offline page metadata, keyed by bookmark IDs.
   std::map<int64, OfflinePageItem> offline_pages_;
 
@@ -314,6 +330,8 @@ class OfflinePageModel : public KeyedService,
   // Delayed tasks that should be invoked after the loading is done.
   std::vector<base::Closure> delayed_tasks_;
 
+  bookmarks::BookmarkModel* bookmarks_model_;
+
   ScopedObserver<bookmarks::BookmarkModel, bookmarks::BookmarkModelObserver>
       scoped_observer_;