Update from https://crrev.com/329939

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 45 matching lines @@
   base::Value* underlay_value = NULL;
   if (!underlay_->GetMutableValue(GetUnderlayKey(key), &underlay_value))
     return false;
 
   *result = underlay_value->DeepCopy();
   overlay_.SetValue(key, *result);
   return true;
 }
 
 void OverlayUserPrefStore::SetValue(const std::string& key,
-                                    base::Value* value) {
+                                    base::Value* value,
+                                    uint32 flags) {
   if (!ShallBeStoredInOverlay(key)) {
-    underlay_->SetValue(GetUnderlayKey(key), value);
+    underlay_->SetValue(GetUnderlayKey(key), value, flags);
     return;
   }
 
   if (overlay_.SetValue(key, value))
-    ReportValueChanged(key);
+    ReportValueChanged(key, flags);
 }
 
 void OverlayUserPrefStore::SetValueSilently(const std::string& key,
-                                            base::Value* value) {
+                                            base::Value* value,
+                                            uint32 flags) {
   if (!ShallBeStoredInOverlay(key)) {
-    underlay_->SetValueSilently(GetUnderlayKey(key), value);
+    underlay_->SetValueSilently(GetUnderlayKey(key), value, flags);
     return;
   }
 
   overlay_.SetValue(key, value);
 }
 
-void OverlayUserPrefStore::RemoveValue(const std::string& key) {
+void OverlayUserPrefStore::RemoveValue(const std::string& key, uint32 flags) {
   if (!ShallBeStoredInOverlay(key)) {
-    underlay_->RemoveValue(GetUnderlayKey(key));
+    underlay_->RemoveValue(GetUnderlayKey(key), flags);
     return;
   }
 
   if (overlay_.RemoveValue(key))
-    ReportValueChanged(key);
+    ReportValueChanged(key, flags);
 }
 
 bool OverlayUserPrefStore::ReadOnly() const {
   return false;
 }
 
 PersistentPrefStore::PrefReadError OverlayUserPrefStore::GetReadError() const {
   return PersistentPrefStore::PREF_READ_ERROR_NONE;
 }
 
 PersistentPrefStore::PrefReadError OverlayUserPrefStore::ReadPrefs() {
   // We do not read intentionally.
   OnInitializationCompleted(true);
   return PersistentPrefStore::PREF_READ_ERROR_NONE;
 }
 
 void OverlayUserPrefStore::ReadPrefsAsync(
     ReadErrorDelegate* error_delegate_raw) {
   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::ReportValueChanged(const std::string& key) {
+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));
+    ReportValueChanged(GetOverlayKey(key), DEFAULT_PREF_WRITE_FLAGS);
 }
 
 void OverlayUserPrefStore::OnInitializationCompleted(bool succeeded) {
   FOR_EACH_OBSERVER(PrefStore::Observer, observers_,
                     OnInitializationCompleted(succeeded));
 }
 
 void OverlayUserPrefStore::RegisterOverlayPref(const std::string& key) {
   RegisterOverlayPref(key, key);
 }
@@ skipping 29 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();
 }