Pass empty cros_user string to GetProfileSyncService() in sync integration tests

chrome/browser/sync/profile_sync_service_harness.cc

Index: chrome/browser/sync/profile_sync_service_harness.cc
diff --git a/chrome/browser/sync/profile_sync_service_harness.cc b/chrome/browser/sync/profile_sync_service_harness.cc
index 4243c4cb7928e3be60ca65e5bbf0264f0da1e689..95eaff179992291f3dd132f4a1a61044bb8f72ec 100644
--- a/chrome/browser/sync/profile_sync_service_harness.cc
+++ b/chrome/browser/sync/profile_sync_service_harness.cc
@@ -130,7 +130,7 @@ bool ProfileSyncServiceHarness::SetupSync() {
 bool ProfileSyncServiceHarness::SetupSync(
     const syncable::ModelTypeSet& synced_datatypes) {
   // Initialize the sync client's profile sync service object.
-  service_ = profile_->GetProfileSyncService();
+  service_ = profile_->GetProfileSyncService("");
   if (service_ == NULL) {
     LOG(ERROR) << "SetupSync(): service_ is null.";
     return false;