[Sync] Add a sanity integration test for USS.

chrome/browser/sync/test/integration/single_client_extensions_sync_test.cc

 // Copyright (c) 2011 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.
 
 #include "base/macros.h"
 #include "chrome/browser/sync/test/integration/await_match_status_change_checker.h"
 #include "chrome/browser/sync/test/integration/extensions_helper.h"
 #include "chrome/browser/sync/test/integration/sync_integration_test_util.h"
 #include "chrome/browser/sync/test/integration/sync_test.h"
 #include "components/browser_sync/browser/profile_sync_service.h"
@@ skipping 64 matching lines @@
 
   // Start with an extension installed, and setup sync.
   InstallExtensionForAllProfiles(0);
   ASSERT_TRUE(SetupSync());
   EXPECT_TRUE(AllProfilesHaveSameExtensionsAsVerifier());
 
   // Simulate a delete at the server.
   std::vector<sync_pb::SyncEntity> server_extensions =
       GetFakeServer()->GetSyncEntitiesByModelType(syncer::EXTENSIONS);
   ASSERT_EQ(1ul, server_extensions.size());
-  std::string entity_id = server_extensions[0].id_string();
   std::unique_ptr<fake_server::FakeServerEntity> tombstone(
-      fake_server::TombstoneEntity::Create(entity_id));
+      fake_server::TombstoneEntity::Create(
+          server_extensions[0].id_string(),
+          server_extensions[0].client_defined_unique_tag()));
   GetFakeServer()->InjectEntity(std::move(tombstone));
 
   // Modify the extension in the local profile to cause a conflict.
   DisableExtension(GetProfile(0), 0);
   EXPECT_EQ(1u, GetInstalledExtensions(GetProfile(0)).size());
 
   // Trigger sync, and expect the extension to remain uninstalled at the server
   // and get uninstalled locally.
   const syncer::ModelTypeSet kExtensionsType(syncer::EXTENSIONS);
   TriggerSyncForModelTypes(0, kExtensionsType);
   server_extensions =
       GetFakeServer()->GetSyncEntitiesByModelType(syncer::EXTENSIONS);
   EXPECT_EQ(0ul, server_extensions.size());
 
   AwaitMatchStatusChangeChecker checker(
       base::Bind(&ExtensionCountCheck, GetProfile(0), 0u),
       "Waiting for profile to have no extensions");
   checker.Wait();
   EXPECT_TRUE(!checker.TimedOut());
   EXPECT_TRUE(GetInstalledExtensions(GetProfile(0)).empty());
 }