Update from https://crrev.com/333737

base/prefs/overlay_user_pref_store.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/prefs/overlay_user_pref_store.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
 
 OverlayUserPrefStore::OverlayUserPrefStore(
@@ skipping 103 matching lines @@
   scoped_ptr<ReadErrorDelegate> error_delegate(error_delegate_raw);
   // We do not read intentionally.
   OnInitializationCompleted(true);
 }
 
 void OverlayUserPrefStore::CommitPendingWrite() {
   underlay_->CommitPendingWrite();
   // We do not write our content intentionally.
 }
 
+void OverlayUserPrefStore::SchedulePendingLossyWrites() {
+  underlay_->SchedulePendingLossyWrites();
+}
+
 void OverlayUserPrefStore::ReportValueChanged(const std::string& key,
                                               uint32 flags) {
   FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
 }
 
 void OverlayUserPrefStore::OnPrefValueChanged(const std::string& key) {
   if (!overlay_.GetValue(GetOverlayKey(key), NULL))
     ReportValueChanged(GetOverlayKey(key), DEFAULT_PREF_WRITE_FLAGS);
 }
 
@@ skipping 37 matching lines @@
   NamesMap::const_iterator i =
       overlay_to_underlay_names_map_.find(overlay_key);
   return i != overlay_to_underlay_names_map_.end() ? i->second : overlay_key;
 }
 
 bool OverlayUserPrefStore::ShallBeStoredInOverlay(
     const std::string& key) const {
   return overlay_to_underlay_names_map_.find(key) !=
       overlay_to_underlay_names_map_.end();
 }