[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 1005 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_;

[pavely, 2017/01/12 00:27:13]

Previously if user signs out this method would return default snapshot. Now it
will return last snapshot. I guess there should be no harm in it.

[maxbogue, 2017/01/12 01:55:02]

Hmm... I'm going to clear it in ShutdownImpl just to be safe.

 }
 
 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