[Sync] Allow sync start without sign-in if the local sync backend is on.

components/sync/engine/test_engine_components_factory.cc

Index: components/sync/engine/test_engine_components_factory.cc
diff --git a/components/sync/engine/test_engine_components_factory.cc b/components/sync/engine/test_engine_components_factory.cc
index 116c6d2bbcc7dd7b7d7792f2a2dda3bace64304d..7a71923358b9002daad1375b06b7d13e655127ae 100644
--- a/components/sync/engine/test_engine_components_factory.cc
+++ b/components/sync/engine/test_engine_components_factory.cc
@@ -25,7 +25,8 @@ TestEngineComponentsFactory::~TestEngineComponentsFactory() {}
 std::unique_ptr<SyncScheduler> TestEngineComponentsFactory::BuildScheduler(
     const std::string& name,
     SyncCycleContext* context,
-    CancelationSignal* cancelation_signal) {
+    CancelationSignal* cancelation_signal,
+    bool local_sync_backend_enabled) {
   return std::unique_ptr<SyncScheduler>(new FakeSyncScheduler());
 }