Provide lazy CommitPendingWrites in addition to eager SavePersistentPrefs.

chrome/browser/prefs/overlay_persistent_pref_store.cc

 // Copyright (c) 2011 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 "chrome/browser/prefs/overlay_persistent_pref_store.h"
 
 OverlayPersistentPrefStore::OverlayPersistentPrefStore(
     PersistentPrefStore* underlay)
     : underlay_(underlay) {
   underlay_->AddObserver(this);
@@ skipping 52 matching lines @@
 
 bool OverlayPersistentPrefStore::WritePrefs() {
   // We do not write intentionally.
   return true;
 }
 
 void OverlayPersistentPrefStore::ScheduleWritePrefs() {
   // We do not write intentionally.
 }
 
+void OverlayPersistentPrefStore::CommitPendingWrite() {
+  // We do not write intentionally.
+}
+
 void OverlayPersistentPrefStore::ReportValueChanged(const std::string& key) {
   FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
 }
 
 void OverlayPersistentPrefStore::OnPrefValueChanged(const std::string& key) {
   if (!overlay_.GetValue(key, NULL))
     FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
 }
 
 void OverlayPersistentPrefStore::OnInitializationCompleted() {
   FOR_EACH_OBSERVER(PrefStore::Observer, observers_,
                     OnInitializationCompleted());
 }