Clean up TestProfileSyncService and related tests

chrome/browser/sync/profile_sync_service.cc

Index: chrome/browser/sync/profile_sync_service.cc
diff --git a/chrome/browser/sync/profile_sync_service.cc b/chrome/browser/sync/profile_sync_service.cc
index 5173ed7c0d765c02a5209aa955e2c9a8cf9a43cc..252fa8467860ce6be2aa26f570bace58971bafeb 100644
--- a/chrome/browser/sync/profile_sync_service.cc
+++ b/chrome/browser/sync/profile_sync_service.cc
@@ -1727,12 +1727,6 @@ bool ProfileSyncService::IsCryptographerReady(
   return backend_.get() && backend_->IsCryptographerReady(trans);
 }
 
-SyncBackendHost* ProfileSyncService::GetBackendForTest() {
-  // We don't check |backend_initialized_|; we assume the test class
-  // knows what it's doing.
-  return backend_.get();
-}
-
 void ProfileSyncService::ConfigurePriorityDataTypes() {
   const syncer::ModelTypeSet priority_types =
       Intersection(GetPreferredDataTypes(), syncer::PriorityUserTypes());