[USS] Move GetAllNodes from backend to controller

components/sync/core_impl/test/fake_sync_manager.cc

Index: components/sync/core_impl/test/fake_sync_manager.cc
diff --git a/components/sync/core_impl/test/fake_sync_manager.cc b/components/sync/core_impl/test/fake_sync_manager.cc
index 9490c229438b101c6f63a00974fb9a020d0dc950..3077ebe22c45ae36ba2811ed43f4a1a80fa6c27a 100644
--- a/components/sync/core_impl/test/fake_sync_manager.cc
+++ b/components/sync/core_impl/test/fake_sync_manager.cc
@@ -226,11 +226,6 @@ FakeSyncManager::GetBufferedProtocolEvents() {
   return std::vector<std::unique_ptr<ProtocolEvent>>();
 }
 
-std::unique_ptr<base::ListValue> FakeSyncManager::GetAllNodesForType(
-    syncer::ModelType type) {
-  return std::unique_ptr<base::ListValue>(new base::ListValue());
-}
-
 void FakeSyncManager::RefreshTypes(ModelTypeSet types) {
   last_refresh_request_types_ = types;
 }