[Sync] Refactoring polling to be reliable.

sync/engine/sync_scheduler_unittest.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 "base/bind.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/memory/weak_ptr.h"
 #include "base/run_loop.h"
 #include "base/test/test_timeouts.h"
@@ skipping 176 matching lines @@
       SCOPED_TRACE(testing::Message() << "SyncShare # (" << i << ")");
       TimeTicks optimal_next_sync = optimal_start + poll_interval * i;
       EXPECT_GE(times[i], optimal_next_sync);
     }
   }
 
   void DoQuitLoopNow() {
     QuitLoopNow();
   }
 
-  void StartSyncScheduler(SyncScheduler::Mode mode) {
-    scheduler()->Start(mode);
+  void StartSyncConfiguration() {
+    scheduler()->Start(SyncScheduler::CONFIGURATION_MODE, base::Time());
+  }
+
+  void StartSyncScheduler(base::Time last_poll_time) {
+    scheduler()->Start(SyncScheduler::NORMAL_MODE, last_poll_time);
   }
 
   // This stops the scheduler synchronously.
   void StopSyncScheduler() {
     base::MessageLoop::current()->PostTask(
         FROM_HERE,
         base::Bind(&SyncSchedulerTest::DoQuitLoopNow,
                    weak_ptr_factory_.GetWeakPtr()));
     RunLoop();
   }
 
   bool RunAndGetBackoff() {
     ModelTypeSet nudge_types(THEMES);
-    StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+    StartSyncScheduler(base::Time());
 
     scheduler()->ScheduleLocalNudge(nudge_types, FROM_HERE);
     RunLoop();
 
     return scheduler()->IsBackingOff();
   }
 
   void UseMockDelayProvider() {
     delay_ = new MockDelayProvider();
     scheduler_->delay_provider_.reset(delay_);
@@ skipping 34 matching lines @@
   std::vector<scoped_refptr<ModelSafeWorker> > workers_;
   scoped_refptr<ExtensionsActivity> extensions_activity_;
   ModelSafeRoutingInfo routing_info_;
   base::WeakPtrFactory<SyncSchedulerTest> weak_ptr_factory_;
 };
 
 void RecordSyncShareImpl(SyncShareTimes* times) {
   times->push_back(TimeTicks::Now());
 }
 
-ACTION_P(RecordSyncShare, times) {
+ACTION_P2(RecordSyncShare, times, success) {
   RecordSyncShareImpl(times);
   if (base::MessageLoop::current()->is_running())
     QuitLoopNow();
-  return true;
+  return success;
 }
 
-ACTION_P2(RecordSyncShareMultiple, times, quit_after) {
+ACTION_P3(RecordSyncShareMultiple, times, quit_after, success) {
   RecordSyncShareImpl(times);
   EXPECT_LE(times->size(), quit_after);
   if (times->size() >= quit_after &&
       base::MessageLoop::current()->is_running()) {
     QuitLoopNow();
   }
-  return true;
+  return success;
 }
 
 ACTION_P(StopScheduler, scheduler) {
   scheduler->Stop();
 }
 
 ACTION(AddFailureAndQuitLoopNow) {
   ADD_FAILURE();
   QuitLoopNow();
   return true;
 }
 
-ACTION(QuitLoopNowAction) {
+ACTION_P(QuitLoopNowAction, success) {
   QuitLoopNow();
-  return true;
+  return success;
 }
 
 // Test nudge scheduling.
 TEST_F(SyncSchedulerTest, Nudge) {
   SyncShareTimes times;
   ModelTypeSet model_types(THEMES);
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times)))
+                      RecordSyncShare(&times, true)))
       .RetiresOnSaturation();
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   scheduler()->ScheduleLocalNudge(model_types, FROM_HERE);
   RunLoop();
 
   Mock::VerifyAndClearExpectations(syncer());
 
   // Make sure a second, later, nudge is unaffected by first (no coalescing).
   SyncShareTimes times2;
   model_types.Remove(THEMES);
   model_types.Put(TYPED_URLS);
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times2)));
+                      RecordSyncShare(&times2, true)));
   scheduler()->ScheduleLocalNudge(model_types, FROM_HERE);
   RunLoop();
 }
 
 // Make sure a regular config command is scheduled fine in the absence of any
 // errors.
 TEST_F(SyncSchedulerTest, Config) {
   SyncShareTimes times;
   const ModelTypeSet model_types(THEMES);
 
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureSuccess),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, true)));
 
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
 
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       model_types,
       TypesToRoutingInfo(model_types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
   PumpLoop();
   ASSERT_EQ(1, ready_counter.times_called());
   ASSERT_EQ(0, retry_counter.times_called());
 }
 
 // Simulate a failure and make sure the config request is retried.
 TEST_F(SyncSchedulerTest, ConfigWithBackingOff) {
   UseMockDelayProvider();
   EXPECT_CALL(*delay(), GetDelay(_))
       .WillRepeatedly(Return(TimeDelta::FromMilliseconds(20)));
   SyncShareTimes times;
   const ModelTypeSet model_types(THEMES);
 
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
 
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureFailed),
-                      RecordSyncShare(&times)))
+                      RecordSyncShare(&times, false)))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureFailed),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, false)));
 
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       model_types,
       TypesToRoutingInfo(model_types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
   RunLoop();
   ASSERT_EQ(0, ready_counter.times_called());
   ASSERT_EQ(1, retry_counter.times_called());
 
   // RunLoop() will trigger TryCanaryJob which will retry configuration.
   // Since retry_task was already called it shouldn't be called again.
   RunLoop();
   ASSERT_EQ(0, ready_counter.times_called());
   ASSERT_EQ(1, retry_counter.times_called());
 
   Mock::VerifyAndClearExpectations(syncer());
 
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureSuccess),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, true)));
   RunLoop();
 
   ASSERT_EQ(1, ready_counter.times_called());
 }
 
 // Simuilate SyncSchedulerImpl::Stop being called in the middle of Configure.
 // This can happen if server returns NOT_MY_BIRTHDAY.
 TEST_F(SyncSchedulerTest, ConfigWithStop) {
   UseMockDelayProvider();
   EXPECT_CALL(*delay(), GetDelay(_))
       .WillRepeatedly(Return(TimeDelta::FromMilliseconds(20)));
   SyncShareTimes times;
   const ModelTypeSet model_types(THEMES);
 
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
 
   // Make ConfigureSyncShare call scheduler->Stop(). It is not supposed to call
   // retry_task or dereference configuration params.
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureFailed),
                       StopScheduler(scheduler()),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, false)));
 
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       model_types,
       TypesToRoutingInfo(model_types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
   PumpLoop();
   ASSERT_EQ(0, ready_counter.times_called());
   ASSERT_EQ(0, retry_counter.times_called());
 }
 
 // Issue a nudge when the config has failed. Make sure both the config and
 // nudge are executed.
 TEST_F(SyncSchedulerTest, NudgeWithConfigWithBackingOff) {
   const ModelTypeSet model_types(THEMES);
   UseMockDelayProvider();
   EXPECT_CALL(*delay(), GetDelay(_))
       .WillRepeatedly(Return(TimeDelta::FromMilliseconds(50)));
   SyncShareTimes times;
 
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
 
   // Request a configure and make sure it fails.
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureFailed),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, false)));
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       model_types,
       TypesToRoutingInfo(model_types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
   RunLoop();
   ASSERT_EQ(0, ready_counter.times_called());
   ASSERT_EQ(1, retry_counter.times_called());
   Mock::VerifyAndClearExpectations(syncer());
 
   // Ask for a nudge while dealing with repeated configure failure.
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureFailed),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, false)));
   scheduler()->ScheduleLocalNudge(model_types, FROM_HERE);
   RunLoop();
   // Note that we're not RunLoop()ing for the NUDGE we just scheduled, but
   // for the first retry attempt from the config job (after
   // waiting ~+/- 50ms).
   Mock::VerifyAndClearExpectations(syncer());
   ASSERT_EQ(0, ready_counter.times_called());
 
   // Let the next configure retry succeed.
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureSuccess),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, true)));
   RunLoop();
 
   // Now change the mode so nudge can execute.
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times)));
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+                      RecordSyncShare(&times, true)));
+  StartSyncScheduler(base::Time());
   PumpLoop();
 }
 
 // Test that nudges are coalesced.
 TEST_F(SyncSchedulerTest, NudgeCoalescing) {
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   SyncShareTimes times;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, true)));
   const ModelTypeSet types1(THEMES), types2(TYPED_URLS), types3(THEMES);
   TimeTicks optimal_time = TimeTicks::Now() + default_delay();
   scheduler()->ScheduleLocalNudge(types1, FROM_HERE);
   scheduler()->ScheduleLocalNudge(types2, FROM_HERE);
   RunLoop();
 
   ASSERT_EQ(1U, times.size());
   EXPECT_GE(times[0], optimal_time);
 
   Mock::VerifyAndClearExpectations(syncer());
 
   SyncShareTimes times2;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times2)));
+                      RecordSyncShare(&times2, true)));
   scheduler()->ScheduleLocalNudge(types3, FROM_HERE);
   RunLoop();
 }
 
 // Test that nudges are coalesced.
 TEST_F(SyncSchedulerTest, NudgeCoalescingWithDifferentTimings) {
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   SyncShareTimes times;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, true)));
   ModelTypeSet types1(THEMES), types2(TYPED_URLS), types3;
 
   // Create a huge time delay.
   TimeDelta delay = TimeDelta::FromDays(1);
 
   std::map<ModelType, TimeDelta> delay_map;
   delay_map[types1.First().Get()] = delay;
   scheduler()->OnReceivedCustomNudgeDelays(delay_map);
   scheduler()->ScheduleLocalNudge(types1, FROM_HERE);
   scheduler()->ScheduleLocalNudge(types2, FROM_HERE);
 
   TimeTicks min_time = TimeTicks::Now();
   TimeTicks max_time = TimeTicks::Now() + delay;
 
   RunLoop();
   Mock::VerifyAndClearExpectations(syncer());
 
   // Make sure the sync happened at the right time.
   ASSERT_EQ(1U, times.size());
   EXPECT_GE(times[0], min_time);
   EXPECT_LE(times[0], max_time);
 }
 
 // Test nudge scheduling.
 TEST_F(SyncSchedulerTest, NudgeWithStates) {
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   SyncShareTimes times1;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times1)))
+                      RecordSyncShare(&times1, true)))
       .RetiresOnSaturation();
   scheduler()->ScheduleInvalidationNudge(
       THEMES, BuildInvalidation(10, "test"), FROM_HERE);
   RunLoop();
 
   Mock::VerifyAndClearExpectations(syncer());
 
   // Make sure a second, later, nudge is unaffected by first (no coalescing).
   SyncShareTimes times2;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times2)));
+                      RecordSyncShare(&times2, true)));
   scheduler()->ScheduleInvalidationNudge(
       TYPED_URLS, BuildInvalidation(10, "test2"), FROM_HERE);
   RunLoop();
 }
 
 // Test that polling works as expected.
 TEST_F(SyncSchedulerTest, Polling) {
   SyncShareTimes times;
   TimeDelta poll_interval(TimeDelta::FromMilliseconds(30));
   EXPECT_CALL(*syncer(), PollSyncShare(_,_)).Times(AtLeast(kMinNumSamples))
       .WillRepeatedly(
           DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
-                RecordSyncShareMultiple(&times, kMinNumSamples)));
+                RecordSyncShareMultiple(&times, kMinNumSamples, true)));
 
   scheduler()->OnReceivedLongPollIntervalUpdate(poll_interval);
 
   TimeTicks optimal_start = TimeTicks::Now() + poll_interval;
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // Run again to wait for polling.
   RunLoop();
+
+  StopSyncScheduler();
+  AnalyzePollRun(times, kMinNumSamples, optimal_start, poll_interval);
+}
+
+// Test that we reuse the previous poll time on startup, triggering the first
+// poll based on when the last one happened. Subsequent polls should have the
+// normal delay.
+TEST_F(SyncSchedulerTest, PollingPersistence) {
+  SyncShareTimes times;
+  // Use a large poll interval that wouldn't normally get hit on its own for
+  // some time yet.
+  TimeDelta poll_interval(TimeDelta::FromMilliseconds(500));
+  EXPECT_CALL(*syncer(), PollSyncShare(_,_)).Times(AtLeast(kMinNumSamples))
+      .WillRepeatedly(
+          DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
+                RecordSyncShareMultiple(&times, kMinNumSamples, true)));
+
+  scheduler()->OnReceivedLongPollIntervalUpdate(poll_interval);
+
+  // Set the start time to now, as the poll was overdue.
+  TimeTicks optimal_start = TimeTicks::Now();
+  StartSyncScheduler(base::Time::Now() - poll_interval);
+
+  // Run again to wait for polling.
+  RunLoop();
+
+  StopSyncScheduler();
+  AnalyzePollRun(times, kMinNumSamples, optimal_start, poll_interval);
+}
+
+// Test that if the persisted poll is in the future, it's ignored (the case
+// where the local time has been modified).
+TEST_F(SyncSchedulerTest, PollingPersistenceBadClock) {
+  SyncShareTimes times;
+  TimeDelta poll_interval(TimeDelta::FromMilliseconds(30));
+  EXPECT_CALL(*syncer(), PollSyncShare(_,_)).Times(AtLeast(kMinNumSamples))
+      .WillRepeatedly(
+          DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
+                RecordSyncShareMultiple(&times, kMinNumSamples, true)));
+
+  scheduler()->OnReceivedLongPollIntervalUpdate(poll_interval);
+
+  // Set the start time to |poll_interval| in the future.
+  TimeTicks optimal_start = TimeTicks::Now() + poll_interval;
+  StartSyncScheduler(base::Time::Now() + base::TimeDelta::FromMinutes(10));
+
+  // Run again to wait for polling.
+  RunLoop();
 
   StopSyncScheduler();
   AnalyzePollRun(times, kMinNumSamples, optimal_start, poll_interval);
 }
 
 // Test that the short poll interval is used.
 TEST_F(SyncSchedulerTest, PollNotificationsDisabled) {
   SyncShareTimes times;
   TimeDelta poll_interval(TimeDelta::FromMilliseconds(30));
   EXPECT_CALL(*syncer(), PollSyncShare(_,_)).Times(AtLeast(kMinNumSamples))
       .WillRepeatedly(
           DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
-                RecordSyncShareMultiple(&times, kMinNumSamples)));
+                RecordSyncShareMultiple(&times, kMinNumSamples, true)));
 
   scheduler()->OnReceivedShortPollIntervalUpdate(poll_interval);
   scheduler()->SetNotificationsEnabled(false);
 
   TimeTicks optimal_start = TimeTicks::Now() + poll_interval;
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // Run again to wait for polling.
   RunLoop();
 
   StopSyncScheduler();
   AnalyzePollRun(times, kMinNumSamples, optimal_start, poll_interval);
 }
 
 // Test that polling intervals are updated when needed.
 TEST_F(SyncSchedulerTest, PollIntervalUpdate) {
   SyncShareTimes times;
   TimeDelta poll1(TimeDelta::FromMilliseconds(120));
   TimeDelta poll2(TimeDelta::FromMilliseconds(30));
   scheduler()->OnReceivedLongPollIntervalUpdate(poll1);
   EXPECT_CALL(*syncer(), PollSyncShare(_,_)).Times(AtLeast(kMinNumSamples))
       .WillOnce(DoAll(
           WithArgs<0,1>(
               sessions::test_util::SimulatePollIntervalUpdate(poll2)),
           Return(true)))
       .WillRepeatedly(
           DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
                 WithArg<1>(
-                    RecordSyncShareMultiple(&times, kMinNumSamples))));
+                    RecordSyncShareMultiple(&times, kMinNumSamples, true))));
 
   TimeTicks optimal_start = TimeTicks::Now() + poll1 + poll2;
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // Run again to wait for polling.
   RunLoop();
 
   StopSyncScheduler();
   AnalyzePollRun(times, kMinNumSamples, optimal_start, poll2);
 }
 
 // Test that no syncing occurs when throttled.
 TEST_F(SyncSchedulerTest, ThrottlingDoesThrottle) {
   const ModelTypeSet types(THEMES);
   TimeDelta poll(TimeDelta::FromMilliseconds(20));
   TimeDelta throttle(TimeDelta::FromMinutes(10));
   scheduler()->OnReceivedLongPollIntervalUpdate(poll);
 
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(
           WithArg<2>(sessions::test_util::SimulateThrottled(throttle)),
-          Return(true)))
+          Return(false)))
       .WillRepeatedly(AddFailureAndQuitLoopNow());
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   scheduler()->ScheduleLocalNudge(types, FROM_HERE);
   PumpLoop();
 
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
 
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       types,
       TypesToRoutingInfo(types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
   PumpLoop();
   ASSERT_EQ(0, ready_counter.times_called());
   ASSERT_EQ(1, retry_counter.times_called());
 
 }
 
 TEST_F(SyncSchedulerTest, ThrottlingExpiresFromPoll) {
   SyncShareTimes times;
   TimeDelta poll(TimeDelta::FromMilliseconds(15));
   TimeDelta throttle1(TimeDelta::FromMilliseconds(150));
   scheduler()->OnReceivedLongPollIntervalUpdate(poll);
 
   ::testing::InSequence seq;
   EXPECT_CALL(*syncer(), PollSyncShare(_,_))
       .WillOnce(DoAll(
           WithArg<1>(sessions::test_util::SimulateThrottled(throttle1)),
-          Return(true)))
+          Return(false)))
       .RetiresOnSaturation();
   EXPECT_CALL(*syncer(), PollSyncShare(_,_))
       .WillRepeatedly(
           DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
-                RecordSyncShareMultiple(&times, kMinNumSamples)));
+                RecordSyncShareMultiple(&times, kMinNumSamples, true)));
 
   TimeTicks optimal_start = TimeTicks::Now() + poll + throttle1;
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // Run again to wait for polling.
   RunLoop();
 
   StopSyncScheduler();
   AnalyzePollRun(times, kMinNumSamples, optimal_start, poll);
 }
 
 TEST_F(SyncSchedulerTest, ThrottlingExpiresFromNudge) {
   SyncShareTimes times;
   TimeDelta poll(TimeDelta::FromDays(1));
   TimeDelta throttle1(TimeDelta::FromMilliseconds(150));
   scheduler()->OnReceivedLongPollIntervalUpdate(poll);
 
   ::testing::InSequence seq;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(
           WithArg<2>(sessions::test_util::SimulateThrottled(throttle1)),
-          Return(true)))
+          Return(false)))
       .RetiresOnSaturation();
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      QuitLoopNowAction()));
+                      QuitLoopNowAction(true)));
 
   const ModelTypeSet types(THEMES);
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
   scheduler()->ScheduleLocalNudge(types, FROM_HERE);
 
   PumpLoop(); // To get PerformDelayedNudge called.
   PumpLoop(); // To get TrySyncSessionJob called
   EXPECT_TRUE(scheduler()->IsCurrentlyThrottled());
   RunLoop();
   EXPECT_FALSE(scheduler()->IsCurrentlyThrottled());
 
   StopSyncScheduler();
 }
 
 TEST_F(SyncSchedulerTest, ThrottlingExpiresFromConfigure) {
   SyncShareTimes times;
   TimeDelta poll(TimeDelta::FromDays(1));
   TimeDelta throttle1(TimeDelta::FromMilliseconds(150));
   scheduler()->OnReceivedLongPollIntervalUpdate(poll);
 
   ::testing::InSequence seq;
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(
           WithArg<2>(sessions::test_util::SimulateThrottled(throttle1)),
-          Return(true)))
+          Return(false)))
       .RetiresOnSaturation();
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureSuccess),
-                      QuitLoopNowAction()));
+                      QuitLoopNowAction(true)));
 
   const ModelTypeSet types(THEMES);
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
 
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       types,
       TypesToRoutingInfo(types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
@@ skipping 17 matching lines @@
   TimeDelta throttle1(TimeDelta::FromSeconds(60));
   scheduler()->OnReceivedLongPollIntervalUpdate(poll);
 
   const ModelTypeSet types(THEMES);
 
   ::testing::InSequence seq;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(
           WithArg<2>(
               sessions::test_util::SimulateTypesThrottled(types, throttle1)),
-          Return(true)))
+          Return(false)))
       .RetiresOnSaturation();
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
   scheduler()->ScheduleLocalNudge(types, FROM_HERE);
   PumpLoop(); // To get PerformDelayedNudge called.
   PumpLoop(); // To get TrySyncSessionJob called
   EXPECT_TRUE(GetThrottledTypes().HasAll(types));
 
   // This won't cause a sync cycle because the types are throttled.
   scheduler()->ScheduleLocalNudge(types, FROM_HERE);
   PumpLoop();
 
   StopSyncScheduler();
@@ skipping 11 matching lines @@
 
   const ModelTypeSet throttled_types(THEMES);
   const ModelTypeSet unthrottled_types(PREFERENCES);
 
   ::testing::InSequence seq;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(
           WithArg<2>(
               sessions::test_util::SimulateTypesThrottled(
                   throttled_types, throttle1)),
-          Return(true)))
+          Return(false)))
       .RetiresOnSaturation();
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
   scheduler()->ScheduleLocalNudge(throttled_types, FROM_HERE);
   PumpLoop(); // To get PerformDelayedNudge called.
   PumpLoop(); // To get TrySyncSessionJob called
   EXPECT_TRUE(GetThrottledTypes().HasAll(throttled_types));
 
   // Ignore invalidations for throttled types.
   scheduler()->ScheduleInvalidationNudge(
       THEMES, BuildInvalidation(10, "test"), FROM_HERE);
   PumpLoop();
 
   // Ignore refresh requests for throttled types.
   scheduler()->ScheduleLocalRefreshRequest(throttled_types, FROM_HERE);
   PumpLoop();
 
   Mock::VerifyAndClearExpectations(syncer());
 
   // Local nudges for non-throttled types will trigger a sync.
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillRepeatedly(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                            RecordSyncShare(&times)));
+                            RecordSyncShare(&times, true)));
   scheduler()->ScheduleLocalNudge(unthrottled_types, FROM_HERE);
   RunLoop();
   Mock::VerifyAndClearExpectations(syncer());
 
   StopSyncScheduler();
 }
 
 // Test nudges / polls don't run in config mode and config tasks do.
 TEST_F(SyncSchedulerTest, ConfigurationMode) {
   TimeDelta poll(TimeDelta::FromMilliseconds(15));
   SyncShareTimes times;
   scheduler()->OnReceivedLongPollIntervalUpdate(poll);
 
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
 
   const ModelTypeSet nudge_types(TYPED_URLS);
   scheduler()->ScheduleLocalNudge(nudge_types, FROM_HERE);
   scheduler()->ScheduleLocalNudge(nudge_types, FROM_HERE);
 
   const ModelTypeSet config_types(THEMES);
 
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConfigureSuccess),
-                      RecordSyncShare(&times)))
+                      RecordSyncShare(&times, true)))
       .RetiresOnSaturation();
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       config_types,
       TypesToRoutingInfo(config_types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
   RunLoop();
   ASSERT_EQ(1, ready_counter.times_called());
   ASSERT_EQ(0, retry_counter.times_called());
 
   Mock::VerifyAndClearExpectations(syncer());
 
   // Switch to NORMAL_MODE to ensure NUDGES were properly saved and run.
   scheduler()->OnReceivedLongPollIntervalUpdate(TimeDelta::FromDays(1));
   SyncShareTimes times2;
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times2)));
+                      RecordSyncShare(&times2, true)));
 
   // TODO(tim): Figure out how to remove this dangerous need to reset
   // routing info between mode switches.
   context()->SetRoutingInfo(routing_info());
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   RunLoop();
   Mock::VerifyAndClearExpectations(syncer());
 }
 
 class BackoffTriggersSyncSchedulerTest : public SyncSchedulerTest {
   void SetUp() override {
     SyncSchedulerTest::SetUp();
     UseMockDelayProvider();
     EXPECT_CALL(*delay(), GetDelay(_))
         .WillRepeatedly(Return(TimeDelta::FromMilliseconds(10)));
   }
 
   void TearDown() override {
     StopSyncScheduler();
     SyncSchedulerTest::TearDown();
   }
 };
 
-// Have the sycner fail during commit.  Expect that the scheduler enters
+// Have the syncer fail during commit.  Expect that the scheduler enters
 // backoff.
 TEST_F(BackoffTriggersSyncSchedulerTest, FailCommitOnce) {
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateCommitFailed),
-                      QuitLoopNowAction()));
+                      QuitLoopNowAction(false)));
   EXPECT_TRUE(RunAndGetBackoff());
 }
 
 // Have the syncer fail during download updates and succeed on the first
 // retry.  Expect that this clears the backoff state.
 TEST_F(BackoffTriggersSyncSchedulerTest, FailDownloadOnceThenSucceed) {
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(
           Invoke(sessions::test_util::SimulateDownloadUpdatesFailed),
-          Return(true)))
+          Return(false)))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      QuitLoopNowAction()));
+                      QuitLoopNowAction(true)));
   EXPECT_FALSE(RunAndGetBackoff());
 }
 
 // Have the syncer fail during commit and succeed on the first retry.  Expect
 // that this clears the backoff state.
 TEST_F(BackoffTriggersSyncSchedulerTest, FailCommitOnceThenSucceed) {
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(
           Invoke(sessions::test_util::SimulateCommitFailed),
-          Return(true)))
+          Return(false)))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      QuitLoopNowAction()));
+                      QuitLoopNowAction(true)));
   EXPECT_FALSE(RunAndGetBackoff());
 }
 
 // Have the syncer fail to download updates and fail again on the retry.
 // Expect this will leave the scheduler in backoff.
 TEST_F(BackoffTriggersSyncSchedulerTest, FailDownloadTwice) {
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(
           Invoke(sessions::test_util::SimulateDownloadUpdatesFailed),
-          Return(true)))
+          Return(false)))
       .WillRepeatedly(DoAll(
-              Invoke(sessions::test_util::SimulateDownloadUpdatesFailed),
-              QuitLoopNowAction()));
+          Invoke(sessions::test_util::SimulateDownloadUpdatesFailed),
+          QuitLoopNowAction(false)));
   EXPECT_TRUE(RunAndGetBackoff());
 }
 
 // Have the syncer fail to get the encryption key yet succeed in downloading
 // updates. Expect this will leave the scheduler in backoff.
 TEST_F(BackoffTriggersSyncSchedulerTest, FailGetEncryptionKey) {
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillOnce(DoAll(
           Invoke(sessions::test_util::SimulateGetEncryptionKeyFailed),
-          Return(true)))
+          Return(false)))
       .WillRepeatedly(DoAll(
-              Invoke(sessions::test_util::SimulateGetEncryptionKeyFailed),
-              QuitLoopNowAction()));
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+          Invoke(sessions::test_util::SimulateGetEncryptionKeyFailed),
+          QuitLoopNowAction(false)));
+  StartSyncConfiguration();
 
   ModelTypeSet types(THEMES);
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       types,
       TypesToRoutingInfo(types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
   RunLoop();
 
   EXPECT_TRUE(scheduler()->IsBackingOff());
 }
 
 // Test that no polls or extraneous nudges occur when in backoff.
 TEST_F(SyncSchedulerTest, BackoffDropsJobs) {
   SyncShareTimes times;
   TimeDelta poll(TimeDelta::FromMilliseconds(10));
   const ModelTypeSet types(THEMES);
   scheduler()->OnReceivedLongPollIntervalUpdate(poll);
   UseMockDelayProvider();
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateCommitFailed),
-                      RecordSyncShareMultiple(&times, 1U)));
+                      RecordSyncShareMultiple(&times, 1U, false)));
   EXPECT_CALL(*delay(), GetDelay(_)).
       WillRepeatedly(Return(TimeDelta::FromDays(1)));
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // This nudge should fail and put us into backoff.  Thanks to our mock
   // GetDelay() setup above, this will be a long backoff.
   scheduler()->ScheduleLocalNudge(types, FROM_HERE);
   RunLoop();
 
   // From this point forward, no SyncShare functions should be invoked.
   Mock::VerifyAndClearExpectations(syncer());
 
   // Wait a while (10x poll interval) so a few poll jobs will be attempted.
   PumpLoopFor(poll * 10);
 
   // Try (and fail) to schedule a nudge.
   scheduler()->ScheduleLocalNudge(types, FROM_HERE);
 
   Mock::VerifyAndClearExpectations(syncer());
   Mock::VerifyAndClearExpectations(delay());
 
   EXPECT_CALL(*delay(), GetDelay(_)).Times(0);
 
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
 
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       types,
       TypesToRoutingInfo(types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
   PumpLoop();
   ASSERT_EQ(0, ready_counter.times_called());
   ASSERT_EQ(1, retry_counter.times_called());
 
 }
 
 // Test that backoff is shaping traffic properly with consecutive errors.
 TEST_F(SyncSchedulerTest, BackoffElevation) {
   SyncShareTimes times;
   UseMockDelayProvider();
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_)).Times(kMinNumSamples)
       .WillRepeatedly(DoAll(Invoke(sessions::test_util::SimulateCommitFailed),
-          RecordSyncShareMultiple(&times, kMinNumSamples)));
+          RecordSyncShareMultiple(&times, kMinNumSamples, false)));
 
   const TimeDelta first = TimeDelta::FromSeconds(kInitialBackoffRetrySeconds);
   const TimeDelta second = TimeDelta::FromMilliseconds(20);
   const TimeDelta third = TimeDelta::FromMilliseconds(30);
   const TimeDelta fourth = TimeDelta::FromMilliseconds(40);
   const TimeDelta fifth = TimeDelta::FromMilliseconds(50);
   const TimeDelta sixth = TimeDelta::FromDays(1);
 
   EXPECT_CALL(*delay(), GetDelay(first)).WillOnce(Return(second))
           .RetiresOnSaturation();
   EXPECT_CALL(*delay(), GetDelay(second)).WillOnce(Return(third))
           .RetiresOnSaturation();
   EXPECT_CALL(*delay(), GetDelay(third)).WillOnce(Return(fourth))
           .RetiresOnSaturation();
   EXPECT_CALL(*delay(), GetDelay(fourth)).WillOnce(Return(fifth))
           .RetiresOnSaturation();
   EXPECT_CALL(*delay(), GetDelay(fifth)).WillOnce(Return(sixth));
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // Run again with a nudge.
   scheduler()->ScheduleLocalNudge(ModelTypeSet(THEMES), FROM_HERE);
   RunLoop();
 
   ASSERT_EQ(kMinNumSamples, times.size());
   EXPECT_GE(times[1] - times[0], second);
   EXPECT_GE(times[2] - times[1], third);
   EXPECT_GE(times[3] - times[2], fourth);
   EXPECT_GE(times[4] - times[3], fifth);
 }
 
 // Test that things go back to normal once a retry makes forward progress.
 TEST_F(SyncSchedulerTest, BackoffRelief) {
   SyncShareTimes times;
-  const TimeDelta poll(TimeDelta::FromMilliseconds(10));
-  scheduler()->OnReceivedLongPollIntervalUpdate(poll);
   UseMockDelayProvider();
 
   const TimeDelta backoff = TimeDelta::FromMilliseconds(10);
   EXPECT_CALL(*delay(), GetDelay(_)).WillOnce(Return(backoff));
 
   // Optimal start for the post-backoff poll party.
   TimeTicks optimal_start = TimeTicks::Now();
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // Kick off the test with a failed nudge.
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateCommitFailed),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, false)));
   scheduler()->ScheduleLocalNudge(ModelTypeSet(THEMES), FROM_HERE);
   RunLoop();
   Mock::VerifyAndClearExpectations(syncer());
   TimeTicks optimal_job_time = optimal_start;
   ASSERT_EQ(1U, times.size());
   EXPECT_GE(times[0], optimal_job_time);
 
   // The retry succeeds.
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(
               Invoke(sessions::test_util::SimulateNormalSuccess),
-              RecordSyncShare(&times)));
+              RecordSyncShare(&times, true)));
   RunLoop();
   Mock::VerifyAndClearExpectations(syncer());
   optimal_job_time = optimal_job_time + backoff;
   ASSERT_EQ(2U, times.size());
   EXPECT_GE(times[1], optimal_job_time);
 
   // Now let the Poll timer do its thing.
   EXPECT_CALL(*syncer(), PollSyncShare(_,_))
       .WillRepeatedly(DoAll(
               Invoke(sessions::test_util::SimulatePollSuccess),
-              RecordSyncShareMultiple(&times, kMinNumSamples)));
+              RecordSyncShareMultiple(&times, kMinNumSamples, true)));
+  const TimeDelta poll(TimeDelta::FromMilliseconds(10));
+  scheduler()->OnReceivedLongPollIntervalUpdate(poll);
+
+  // The new optimal time is now, since the desired poll should have happened
+  // in the past.
+  optimal_job_time = base::TimeTicks::Now();
   RunLoop();
   Mock::VerifyAndClearExpectations(syncer());
   ASSERT_EQ(kMinNumSamples, times.size());
   for (size_t i = 2; i < times.size(); i++) {
-    optimal_job_time = optimal_job_time + poll;
     SCOPED_TRACE(testing::Message() << "SyncShare # (" << i << ")");
     EXPECT_GE(times[i], optimal_job_time);
+    optimal_job_time = optimal_job_time + poll;
   }
 
   StopSyncScheduler();
 }
 
-// Test that poll failures are ignored.  They should have no effect on
-// subsequent poll attempts, nor should they trigger a backoff/retry.
+// Test that poll failures are treated like any other failure. They should
+// result in retry with backoff.
 TEST_F(SyncSchedulerTest, TransientPollFailure) {
   SyncShareTimes times;
   const TimeDelta poll_interval(TimeDelta::FromMilliseconds(10));
   scheduler()->OnReceivedLongPollIntervalUpdate(poll_interval);
   UseMockDelayProvider(); // Will cause test failure if backoff is initiated.
+  EXPECT_CALL(*delay(), GetDelay(_))
+      .WillRepeatedly(Return(TimeDelta::FromMilliseconds(0)));
 
   EXPECT_CALL(*syncer(), PollSyncShare(_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulatePollFailed),
-                      RecordSyncShare(&times)))
+                      RecordSyncShare(&times, false)))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, true)));
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // Run the unsucessful poll. The failed poll should not trigger backoff.
   RunLoop();
-  EXPECT_FALSE(scheduler()->IsBackingOff());
+  EXPECT_TRUE(scheduler()->IsBackingOff());
 
   // Run the successful poll.
   RunLoop();
   EXPECT_FALSE(scheduler()->IsBackingOff());
 }
 
 // Test that starting the syncer thread without a valid connection doesn't
 // break things when a connection is detected.
 TEST_F(SyncSchedulerTest, StartWhenNotConnected) {
   connection()->SetServerNotReachable();
   connection()->UpdateConnectionStatus();
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
     .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConnectionFailure),
-                    Return(true)))
+                    Return(false)))
     .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
                     Return(true)));
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   scheduler()->ScheduleLocalNudge(ModelTypeSet(THEMES), FROM_HERE);
   // Should save the nudge for until after the server is reachable.
   base::RunLoop().RunUntilIdle();
 
   scheduler()->OnConnectionStatusChange();
   connection()->SetServerReachable();
   connection()->UpdateConnectionStatus();
   base::RunLoop().RunUntilIdle();
 }
 
 TEST_F(SyncSchedulerTest, ServerConnectionChangeDuringBackoff) {
   UseMockDelayProvider();
   EXPECT_CALL(*delay(), GetDelay(_))
       .WillRepeatedly(Return(TimeDelta::FromMilliseconds(0)));
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
   connection()->SetServerNotReachable();
   connection()->UpdateConnectionStatus();
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
     .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConnectionFailure),
-                    Return(true)))
+                    Return(false)))
     .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
                     Return(true)));
 
   scheduler()->ScheduleLocalNudge(ModelTypeSet(THEMES), FROM_HERE);
   PumpLoop(); // To get PerformDelayedNudge called.
   PumpLoop(); // Run the nudge, that will fail and schedule a quick retry.
   ASSERT_TRUE(scheduler()->IsBackingOff());
 
   // Before we run the scheduled canary, trigger a server connection change.
   scheduler()->OnConnectionStatusChange();
   connection()->SetServerReachable();
   connection()->UpdateConnectionStatus();
   base::RunLoop().RunUntilIdle();
 }
 
 // This was supposed to test the scenario where we receive a nudge while a
 // connection change canary is scheduled, but has not run yet.  Since we've made
 // the connection change canary synchronous, this is no longer possible.
 TEST_F(SyncSchedulerTest, ConnectionChangeCanaryPreemptedByNudge) {
   UseMockDelayProvider();
   EXPECT_CALL(*delay(), GetDelay(_))
       .WillRepeatedly(Return(TimeDelta::FromMilliseconds(0)));
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
   connection()->SetServerNotReachable();
   connection()->UpdateConnectionStatus();
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
     .WillOnce(DoAll(Invoke(sessions::test_util::SimulateConnectionFailure),
-                    Return(true)))
+                    Return(false)))
     .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
                     Return(true)))
     .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                    QuitLoopNowAction()));
+                    QuitLoopNowAction(true)));
 
   scheduler()->ScheduleLocalNudge(ModelTypeSet(THEMES), FROM_HERE);
 
   PumpLoop(); // To get PerformDelayedNudge called.
   PumpLoop(); // Run the nudge, that will fail and schedule a quick retry.
   ASSERT_TRUE(scheduler()->IsBackingOff());
 
   // Before we run the scheduled canary, trigger a server connection change.
   scheduler()->OnConnectionStatusChange();
   PumpLoop();
   connection()->SetServerReachable();
   connection()->UpdateConnectionStatus();
   scheduler()->ScheduleLocalNudge(ModelTypeSet(THEMES), FROM_HERE);
   base::RunLoop().RunUntilIdle();
 }
 
 // Tests that we don't crash trying to run two canaries at once if we receive
 // extra connection status change notifications.  See crbug.com/190085.
 TEST_F(SyncSchedulerTest, DoubleCanaryInConfigure) {
   EXPECT_CALL(*syncer(), ConfigureSyncShare(_,_,_))
       .WillRepeatedly(DoAll(
               Invoke(sessions::test_util::SimulateConfigureConnectionFailure),
               Return(true)));
-  StartSyncScheduler(SyncScheduler::CONFIGURATION_MODE);
+  StartSyncConfiguration();
   connection()->SetServerNotReachable();
   connection()->UpdateConnectionStatus();
 
   ModelTypeSet model_types(THEMES);
   CallbackCounter ready_counter;
   CallbackCounter retry_counter;
   ConfigurationParams params(
       GetUpdatesCallerInfo::RECONFIGURATION,
       model_types,
       TypesToRoutingInfo(model_types),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&ready_counter)),
       base::Bind(&CallbackCounter::Callback, base::Unretained(&retry_counter)));
   scheduler()->ScheduleConfiguration(params);
 
   scheduler()->OnConnectionStatusChange();
   scheduler()->OnConnectionStatusChange();
 
   PumpLoop();  // Run the nudge, that will fail and schedule a quick retry.
 }
 
 TEST_F(SyncSchedulerTest, PollFromCanaryAfterAuthError) {
   SyncShareTimes times;
   TimeDelta poll(TimeDelta::FromMilliseconds(15));
   scheduler()->OnReceivedLongPollIntervalUpdate(poll);
 
   ::testing::InSequence seq;
   EXPECT_CALL(*syncer(), PollSyncShare(_,_))
       .WillRepeatedly(
           DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
-                RecordSyncShareMultiple(&times, kMinNumSamples)));
+                RecordSyncShareMultiple(&times, kMinNumSamples, true)));
 
   connection()->SetServerStatus(HttpResponse::SYNC_AUTH_ERROR);
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   // Run to wait for polling.
   RunLoop();
 
   // Normally OnCredentialsUpdated calls TryCanaryJob that doesn't run Poll,
   // but after poll finished with auth error from poll timer it should retry
   // poll once more
   EXPECT_CALL(*syncer(), PollSyncShare(_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulatePollSuccess),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, true)));
   scheduler()->OnCredentialsUpdated();
   connection()->SetServerStatus(HttpResponse::SERVER_CONNECTION_OK);
   RunLoop();
   StopSyncScheduler();
 }
 
 TEST_F(SyncSchedulerTest, SuccessfulRetry) {
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   SyncShareTimes times;
   base::TimeDelta delay = base::TimeDelta::FromMilliseconds(10);
   scheduler()->OnReceivedGuRetryDelay(delay);
   EXPECT_EQ(delay, GetRetryTimerDelay());
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(
           DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                RecordSyncShare(&times)));
+                RecordSyncShare(&times, true)));
 
   // Run to wait for retrying.
   RunLoop();
 
   StopSyncScheduler();
 }
 
 TEST_F(SyncSchedulerTest, FailedRetry) {
+  SyncShareTimes times;
+
   UseMockDelayProvider();
   EXPECT_CALL(*delay(), GetDelay(_))
       .WillRepeatedly(Return(TimeDelta::FromMilliseconds(10)));
 
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   base::TimeDelta delay = base::TimeDelta::FromMilliseconds(10);
   scheduler()->OnReceivedGuRetryDelay(delay);
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(
           DoAll(Invoke(sessions::test_util::SimulateDownloadUpdatesFailed),
-                QuitLoopNowAction()));
+                RecordSyncShare(&times, false)));
 
   // Run to wait for retrying.
   RunLoop();
 
   EXPECT_TRUE(scheduler()->IsBackingOff());
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(
           DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                QuitLoopNowAction()));
+                RecordSyncShare(&times, true)));
 
   // Run to wait for second retrying.
   RunLoop();
 
   StopSyncScheduler();
 }
 
 ACTION_P2(VerifyRetryTimerDelay, scheduler_test, expected_delay) {
   EXPECT_EQ(expected_delay, scheduler_test->GetRetryTimerDelay());
 }
 
 TEST_F(SyncSchedulerTest, ReceiveNewRetryDelay) {
-  StartSyncScheduler(SyncScheduler::NORMAL_MODE);
+  StartSyncScheduler(base::Time());
 
   SyncShareTimes times;
   base::TimeDelta delay1 = base::TimeDelta::FromMilliseconds(100);
   base::TimeDelta delay2 = base::TimeDelta::FromMilliseconds(200);
 
   scheduler()->ScheduleLocalNudge(ModelTypeSet(THEMES), FROM_HERE);
   scheduler()->OnReceivedGuRetryDelay(delay1);
   EXPECT_EQ(delay1, GetRetryTimerDelay());
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(
           WithoutArgs(VerifyRetryTimerDelay(this, delay1)),
           WithArg<2>(sessions::test_util::SimulateGuRetryDelayCommand(delay2)),
-          RecordSyncShare(&times)));
+          RecordSyncShare(&times, true)));
 
   // Run nudge GU.
   RunLoop();
   EXPECT_EQ(delay2, GetRetryTimerDelay());
 
   EXPECT_CALL(*syncer(), NormalSyncShare(_,_,_))
       .WillOnce(DoAll(Invoke(sessions::test_util::SimulateNormalSuccess),
-                      RecordSyncShare(&times)));
+                      RecordSyncShare(&times, true)));
 
   // Run to wait for retrying.
   RunLoop();
 
   StopSyncScheduler();
 }
 
 }  // namespace syncer