sync: use progress markers instead of timestamps during GetUpdates

chrome/browser/sync/syncable/directory_backing_store.h

 // Copyright (c) 2010 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_SYNC_SYNCABLE_DIRECTORY_BACKING_STORE_H_
 #define CHROME_BROWSER_SYNC_SYNCABLE_DIRECTORY_BACKING_STORE_H_
 #pragma once
 
 #include <string>
 
@@ skipping 63 matching lines @@
   virtual bool SaveChanges(const Directory::SaveChangesSnapshot& snapshot);
 
  private:
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion67To68);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion68To69);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion69To70);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion70To71);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion71To72);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion72To73);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion73To74);
+  FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion74To75);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, ModelTypeIds);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, Corruption);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, DeleteEntries);
   FRIEND_TEST_ALL_PREFIXES(MigrationTest, ToCurrentVersion);
   friend class MigrationTest;
 
   // General Directory initialization and load helpers.
   DirOpenResult InitializeTables();
   // Returns an sqlite return code, usually SQLITE_DONE.
   int CreateTables();
 
   // Create 'share_info' or 'temp_share_info' depending on value of
   // is_temporary. Returns an sqlite
   // return code, SQLITE_DONE on success.
   int CreateShareInfoTable(bool is_temporary);
 
   int CreateShareInfoTableVersion71(bool is_temporary);
   // Create 'metas' or 'temp_metas' depending on value of is_temporary.
   // Returns an sqlite return code, SQLITE_DONE on success.
   int CreateMetasTable(bool is_temporary);
   // Returns an sqlite return code, SQLITE_DONE on success.
   int CreateModelsTable();
+  int CreateV71ModelsTable();
 
   // We don't need to load any synced and applied deleted entries, we can
   // in fact just purge them forever on startup.
   bool DropDeletedEntries();
   // Drops a table if it exists, harmless if the table did not already exist.
   int SafeDropTable(const char* table_name);
 
   // Load helpers for entries and attributes.
   bool LoadEntries(MetahandlesIndex* entry_bucket);
   bool LoadInfo(Directory::KernelLoadInfo* info);
@@ skipping 24 matching lines @@
   // Lazy creation of save_dbhandle_ for use by SaveChanges code path.
   sqlite3* LazyGetSaveHandle();
 
   // Drop all tables in preparation for reinitialization.
   void DropAllTables();
 
   // Serialization helpers for syncable::ModelType.  These convert between
   // the ModelType enum and the values we persist in the database to identify
   // a model.  We persist a default instance of the specifics protobuf as the
   // ID, rather than the enum value.
-  static ModelType ModelIdToModelTypeEnum(const string& model_id);
+  static ModelType ModelIdToModelTypeEnum(const void* data, int length);
   static string ModelTypeEnumToModelId(ModelType model_type);
 
   // Runs an integrity check on the current database.  If the
   // integrity check fails, false is returned and error is populated
   // with an error message.
   bool CheckIntegrity(sqlite3* handle, string* error) const;
 
   // Migration utilities.
   bool AddColumn(const ColumnSpec* column);
   bool RefreshColumns();
   bool SetVersion(int version);
   int GetVersion();
   bool MigrateToSpecifics(const char* old_columns,
                           const char* specifics_column,
                           void(*handler_function) (
                               SQLStatement* old_value_query,
                               int old_value_column,
                               sync_pb::EntitySpecifics* mutable_new_value));
 
   // Individual version migrations.
   bool MigrateVersion67To68();
   bool MigrateVersion68To69();
   bool MigrateVersion69To70();
   bool MigrateVersion70To71();
   bool MigrateVersion71To72();
   bool MigrateVersion72To73();
   bool MigrateVersion73To74();
+  bool MigrateVersion74To75();
 
   // The handle to our sqlite on-disk store for initialization and loading, and
   // for saving changes periodically via SaveChanges, respectively.
   // TODO(timsteele): We should only have one handle here.  The reason we need
   // two at the moment is because the DB can be opened by either the AuthWatcher
   // or SyncCore threads, but SaveChanges is always called by the latter.  We
   // need to change initialization so the DB is only accessed from one thread.
   sqlite3* load_dbhandle_;
   sqlite3* save_dbhandle_;
 
   std::string dir_name_;
   FilePath backing_filepath_;
 
   // Set to true if migration left some old columns around that need to be
   // discarded.
   bool needs_column_refresh_;
 
   DISALLOW_COPY_AND_ASSIGN(DirectoryBackingStore);
 };
 
 }  // namespace syncable
 
 #endif  // CHROME_BROWSER_SYNC_SYNCABLE_DIRECTORY_BACKING_STORE_H_