[Sync] Move snapshot cache from SBHI to PSS.

components/browser_sync/profile_sync_service.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/browser_sync/profile_sync_service.h"
 
 #include <stddef.h>
 
 #include <cstddef>
 #include <map>
@@ skipping 764 matching lines @@
   sync_enabled_weak_factory_.InvalidateWeakPtrs();
 
   startup_controller_->Reset(GetRegisteredDataTypes());
 
   // If the sync DB is getting destroyed, the local DeviceInfo is no longer
   // valid and should be cleared from the cache.
   if (reason == syncer::ShutdownReason::DISABLE_SYNC) {
     local_device_->Clear();
   }
 
-  // Clear various flags.
+  // Clear various state.
   expect_sync_configuration_aborted_ = false;
   is_auth_in_progress_ = false;
   engine_initialized_ = false;
   cached_passphrase_.clear();
   encryption_pending_ = false;
   encrypt_everything_ = false;
   encrypted_types_ = syncer::SyncEncryptionHandler::SensitiveTypes();
   passphrase_required_reason_ = syncer::REASON_PASSPHRASE_NOT_REQUIRED;
   catch_up_configure_in_progress_ = false;
   access_token_.clear();
   request_access_token_retry_timer_.Stop();
+  last_snapshot_ = syncer::SyncCycleSnapshot();
   // Revert to "no auth error".
   if (last_auth_error_.state() != GoogleServiceAuthError::NONE)
     UpdateAuthErrorState(GoogleServiceAuthError::AuthErrorNone());
 
   NotifyObservers();
 
   // Mark this as a clean shutdown(without crash).
   sync_prefs_.SetCleanShutdown(true);
 }
 
@@ skipping 209 matching lines @@
     OnGaiaAccountsInCookieUpdated(accounts, signed_out_accounts, error);
   }
 
   NotifyObservers();
 
   // Nobody will call us to start if no sign in is going to happen.
   if (IsLocalSyncEnabled())
     RequestStart();
 }
 
-void ProfileSyncService::OnSyncCycleCompleted() {
+void ProfileSyncService::OnSyncCycleCompleted(
+    const syncer::SyncCycleSnapshot& snapshot) {
   DCHECK(thread_checker_.CalledOnValidThread());
+
+  last_snapshot_ = snapshot;
+
   UpdateLastSyncedTime();
-  const syncer::SyncCycleSnapshot snapshot = GetLastCycleSnapshot();
+  if (!snapshot.poll_finish_time().is_null())
+    sync_prefs_.SetLastPollTime(snapshot.poll_finish_time());
+
   if (IsDataTypeControllerRunning(syncer::SESSIONS) &&
       snapshot.model_neutral_state().get_updates_request_types.Has(
           syncer::SESSIONS) &&
       !syncer::HasSyncerError(snapshot.model_neutral_state())) {
     // Trigger garbage collection of old sessions now that we've downloaded
     // any new session data.
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&SessionsSyncManager::DoGarbageCollection,
                               base::AsWeakPtr(sessions_sync_manager_.get())));
   }
@@ skipping 819 matching lines @@
   DCHECK(thread_checker_.CalledOnValidThread());
   if (engine_ && engine_initialized_) {
     return engine_->GetUserShare();
   }
   NOTREACHED();
   return nullptr;
 }
 
 syncer::SyncCycleSnapshot ProfileSyncService::GetLastCycleSnapshot() const {
   DCHECK(thread_checker_.CalledOnValidThread());
-  if (engine_)
-    return engine_->GetLastCycleSnapshot();
-  return syncer::SyncCycleSnapshot();
+  return last_snapshot_;
 }
 
 bool ProfileSyncService::HasUnsyncedItems() const {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (HasSyncingEngine() && engine_initialized_) {
     return engine_->HasUnsyncedItems();
   }
   NOTREACHED();
   return false;
 }
@@ skipping 746 matching lines @@
 
   DCHECK(startup_controller_->IsSetupInProgress());
   startup_controller_->SetSetupInProgress(false);
 
   if (IsEngineInitialized())
     ReconfigureDatatypeManager();
   NotifyObservers();
 }
 
 }  // namespace browser_sync