Disable sync promo when RestoreOnStartupURLs policy is used

chrome/browser/prefs/session_startup_pref.cc

Index: chrome/browser/prefs/session_startup_pref.cc
diff --git a/chrome/browser/prefs/session_startup_pref.cc b/chrome/browser/prefs/session_startup_pref.cc
index d8f22ca4e4191c89d42869c8d8b08e8cd101b0ee..6ca978e13e3914d1ca1467c4364346747a7aaaf3 100644
--- a/chrome/browser/prefs/session_startup_pref.cc
+++ b/chrome/browser/prefs/session_startup_pref.cc
@@ -202,6 +202,15 @@ bool SessionStartupPref::URLsAreManaged(PrefService* prefs) {
 }
 
 // static
+bool SessionStartupPref::TypeIsDefault(PrefService* prefs) {
+  DCHECK(prefs);
+  const PrefService::Preference* pref_restore =
+      prefs->FindPreference(prefs::kRestoreOnStartup);
+  DCHECK(pref_restore);
+  return pref_restore->IsDefaultValue();
+}
+
+// static
 SessionStartupPref::Type SessionStartupPref::PrefValueToType(int pref_value) {
   switch (pref_value) {
     case kPrefValueLast:     return SessionStartupPref::LAST;