[Sync] Sync client should to exponential backoff when receive partial failure

components/sync/engine_impl/cycle/test_util.cc

 // Copyright (c) 2012 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 "components/sync/engine_impl/cycle/test_util.h"
 
 #include <map>
 
 namespace syncer {
 namespace test_util {
@@ skipping 79 matching lines @@
 
 void SimulateThrottledImpl(SyncCycle* cycle, const base::TimeDelta& delta) {
   cycle->mutable_status_controller()->set_last_download_updates_result(
       SERVER_RETURN_THROTTLED);
   cycle->delegate()->OnThrottled(delta);
 }
 
 void SimulateTypesThrottledImpl(SyncCycle* cycle,
                                 ModelTypeSet types,
                                 const base::TimeDelta& delta) {
-  cycle->mutable_status_controller()->set_last_download_updates_result(
-      SERVER_RETURN_THROTTLED);
+  cycle->mutable_status_controller()->set_commit_result(
+      SERVER_RETURN_PARTIAL_FAILURE);
   cycle->delegate()->OnTypesThrottled(types, delta);
 }
 
+void SimulatePartialFailureImpl(SyncCycle* cycle, ModelTypeSet types) {
+  cycle->mutable_status_controller()->set_commit_result(
+      SERVER_RETURN_PARTIAL_FAILURE);
+  cycle->delegate()->OnTypesBackedOff(types);
+}
+
 void SimulatePollIntervalUpdateImpl(ModelTypeSet requested_types,
                                     SyncCycle* cycle,
                                     const base::TimeDelta& new_poll) {
   SimulatePollSuccess(requested_types, cycle);
   cycle->delegate()->OnReceivedLongPollIntervalUpdate(new_poll);
 }
 
 void SimulateSessionsCommitDelayUpdateImpl(ModelTypeSet requested_types,
                                            NudgeTracker* nudge_tracker,
                                            SyncCycle* cycle,
                                            const base::TimeDelta& new_delay) {
   SimulateNormalSuccess(requested_types, nudge_tracker, cycle);
   std::map<ModelType, base::TimeDelta> delay_map;
   delay_map[SESSIONS] = new_delay;
   cycle->delegate()->OnReceivedCustomNudgeDelays(delay_map);
 }
 
 void SimulateGuRetryDelayCommandImpl(SyncCycle* cycle, base::TimeDelta delay) {
   cycle->mutable_status_controller()->set_last_download_updates_result(
       SYNCER_OK);
   cycle->delegate()->OnReceivedGuRetryDelay(delay);
 }
 
 }  // namespace test_util
 }  // namespace syncer