[Sync] Make BookmarkChangeProcessor resilient against updates before add

chrome/browser/sync/profile_sync_service_bookmark_unittest.cc

 // Copyright (c) 2012 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.
 
 // TODO(akalin): This file is basically just a unit test for
 // BookmarkChangeProcessor.  Write unit tests for
 // BookmarkModelAssociator separately.
 
 #include <map>
 #include <queue>
@@ skipping 707 matching lines @@
     return
         model_associator_->GetSyncIdFromChromeId(model_->other_node()->id());
   }
 
   int64 bookmark_bar_id() {
     return model_associator_->GetSyncIdFromChromeId(
         model_->bookmark_bar_node()->id());
   }
 
  protected:
+  TestingProfile profile_;
   BookmarkModel* model_;
   syncer::TestUserShare test_user_share_;
   scoped_ptr<BookmarkChangeProcessor> change_processor_;
   StrictMock<DataTypeErrorHandlerMock> mock_error_handler_;
   scoped_ptr<BookmarkModelAssociator> model_associator_;
 
  private:
   // Used by both |ui_thread_| and |file_thread_|.
   base::MessageLoop message_loop_;
   content::TestBrowserThread ui_thread_;
   // Needed by |model_|.
   content::TestBrowserThread file_thread_;
 
   syncer::SyncMergeResult local_merge_result_;
   syncer::SyncMergeResult syncer_merge_result_;
-
-  TestingProfile profile_;
 };
 
 TEST_F(ProfileSyncServiceBookmarkTest, InitialState) {
   LoadBookmarkModel(DELETE_EXISTING_STORAGE, DONT_SAVE_TO_STORAGE);
   StartSync();
 
   EXPECT_TRUE(other_bookmarks_id());
   EXPECT_TRUE(bookmark_bar_id());
   EXPECT_TRUE(mobile_bookmarks_id());
 
@@ skipping 1374 matching lines @@
 
   // Now shut down sync and artificially increment the native model's version.
   StopSync();
   int64 root_version = initial_versions[model_->root_node()->id()];
   model_->SetNodeSyncTransactionVersion(model_->root_node(), root_version + 1);
 
   // Upon association, bookmarks should fail to associate.
   EXPECT_FALSE(AssociateModels());
 }
 
+// It's possible for update/add calls from the bookmark model to be out of
+// order, or asynchronous. Handle that without triggering an error.
+TEST_F(ProfileSyncServiceBookmarkTest, UpdateThenAdd) {
+  LoadBookmarkModel(DELETE_EXISTING_STORAGE, DONT_SAVE_TO_STORAGE);
+  StartSync();
+
+  EXPECT_TRUE(other_bookmarks_id());
+  EXPECT_TRUE(bookmark_bar_id());
+  EXPECT_TRUE(mobile_bookmarks_id());
+
+  ExpectModelMatch();
+
+  // Now destroy the change processor then add a bookmark, to simulate
+  // missing the Update call.
+  change_processor_.reset();
+  const BookmarkNode* node = model_->AddURL(model_->bookmark_bar_node(),
+                                            0,
+                                            base::ASCIIToUTF16("title"),
+                                            GURL("http://www.url.com"));
+
+  // Recreate the change processor then update that bookmark. Sync should
+  // receive the update call and gracefully treat that as if it were an add.
+  change_processor_.reset(new BookmarkChangeProcessor(
+      &profile_, model_associator_.get(), &mock_error_handler_));
+  change_processor_->Start(test_user_share_.user_share());
+  model_->SetTitle(node, base::ASCIIToUTF16("title2"));
+  ExpectModelMatch();
+
+  // Then simulate the add call arriving late.
+  change_processor_->BookmarkNodeAdded(model_, model_->bookmark_bar_node(), 0);
+  ExpectModelMatch();
+}
+
 }  // namespace
 
 }  // namespace browser_sync