Sync: Avoid 3 passes over SyncDarta DB when loading the directory from the disk

sync/test/test_directory_backing_store.h

Index: sync/test/test_directory_backing_store.h
diff --git a/sync/test/test_directory_backing_store.h b/sync/test/test_directory_backing_store.h
index 541528ee48405c706bca45043c3fcba2af16157b..1e718168ca080fdd47392254c7dd2cb90774c697 100644
--- a/sync/test/test_directory_backing_store.h
+++ b/sync/test/test_directory_backing_store.h
@@ -27,8 +27,9 @@ class TestDirectoryBackingStore : public DirectoryBackingStore {
   ~TestDirectoryBackingStore() override;
   DirOpenResult Load(Directory::MetahandlesMap* handles_map,
                      JournalIndex* delete_journals,
+                     MetahandleSet* metahandles_to_purge,
                      Directory::KernelLoadInfo* kernel_load_info) override;
-
+  bool DeleteEntries(const MetahandleSet& handles);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion67To68);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion68To69);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion69To70);