Store the "browser autorestarted, last session must be restored" information in a preference.

chrome/common/pref_names.h

 // 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.
 
 // Constants for the names of various preferences, for easier changing.
 
 #ifndef CHROME_COMMON_PREF_NAMES_H_
 #define CHROME_COMMON_PREF_NAMES_H_
 #pragma once
 
@@ skipping 401 matching lines @@
 extern const char kLastKnownIntranetRedirectOrigin[];
 
 extern const char kCountryIDAtInstall[];
 extern const char kGeoIDAtInstall[];  // OBSOLETE
 
 extern const char kShutdownType[];
 extern const char kShutdownNumProcesses[];
 extern const char kShutdownNumProcessesSlow[];
 
 extern const char kRestartLastSessionOnShutdown[];
+extern const char kWasRestarted[];
 
 extern const char kNumBookmarksOnBookmarkBar[];
 extern const char kNumFoldersOnBookmarkBar[];
 extern const char kNumBookmarksInOtherBookmarkFolder[];
 extern const char kNumFoldersInOtherBookmarkFolder[];
 
 extern const char kNumKeywords[];
 
 extern const char kDisableVideoAndChat[];
 
@@ skipping 185 matching lines @@
 
 extern const char kDevicePolicyRefreshRate[];
 extern const char kUserPolicyRefreshRate[];
 
 extern const char kRecoveryComponentVersion[];
 extern const char kComponentUpdaterState[];
 
 }  // namespace prefs
 
 #endif  // CHROME_COMMON_PREF_NAMES_H_