Migrate startup URLs pref.

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index 1ff7bdea70add955325ad4ac95abb3b47de65858..b1762a996d878a89658908b0207717d14f8cce51 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -82,7 +82,11 @@ const char kRestoreOnStartupMigrated[] = "session.restore_on_startup_migrated";
 
 // The URLs to restore on startup or when the home button is pressed. The URLs
 // are only restored on startup if kRestoreOnStartup is 4.
-const char kURLsToRestoreOnStartup[] = "session.urls_to_restore_on_startup";
+const char kURLsToRestoreOnStartup[] = "session.startup_urls";
+
+// Old startup url pref and migration time delta as a double.
+const char kURLsToRestoreOnStartupOld[] = "session.urls_to_restore_on_startup";
+const char kRestoreStartupURLsMigrated[] = "session.startup_urls_migrated";
 
 // The application locale.
 // For OS_CHROMEOS we maintain kApplicationLocale property in both local state