Refactor preference syncing.

chrome/browser/extensions/extension_prefs.cc

Index: chrome/browser/extensions/extension_prefs.cc
diff --git a/chrome/browser/extensions/extension_prefs.cc b/chrome/browser/extensions/extension_prefs.cc
index bf79d142557b51e80a1d1c9dc3468e0d2dc7376e..def6bb6957a15fbd93bdef5293ddce2c00ab15da 100644
--- a/chrome/browser/extensions/extension_prefs.cc
+++ b/chrome/browser/extensions/extension_prefs.cc
@@ -1547,12 +1547,20 @@ bool ExtensionPrefs::HasIncognitoPrefValue(const std::string& pref_key) {
 
 // static
 void ExtensionPrefs::RegisterUserPrefs(PrefService* prefs) {
-  prefs->RegisterDictionaryPref(kExtensionsPref);
-  prefs->RegisterListPref(kExtensionToolbar);
-  prefs->RegisterIntegerPref(prefs::kExtensionToolbarSize, -1);
-  prefs->RegisterDictionaryPref(kExtensionsBlacklistUpdate);
-  prefs->RegisterListPref(prefs::kExtensionInstallAllowList);
-  prefs->RegisterListPref(prefs::kExtensionInstallDenyList);
-  prefs->RegisterListPref(prefs::kExtensionInstallForceList);
-  prefs->RegisterStringPref(kWebStoreLogin, std::string() /* default_value */);
+  prefs->RegisterDictionaryPref(kExtensionsPref, false /* don't sync pref */);
+  prefs->RegisterListPref(kExtensionToolbar, false /* don't sync pref */);
+  prefs->RegisterIntegerPref(prefs::kExtensionToolbarSize,
+                             -1,
+                             false /* don't sync pref */);
+  prefs->RegisterDictionaryPref(kExtensionsBlacklistUpdate,
+                                false /* don't sync pref */);
+  prefs->RegisterListPref(prefs::kExtensionInstallAllowList,
+                          false /* don't sync pref */);
+  prefs->RegisterListPref(prefs::kExtensionInstallDenyList,
+                          false /* don't sync pref */);
+  prefs->RegisterListPref(prefs::kExtensionInstallForceList,
+                          false /* don't sync pref */);
+  prefs->RegisterStringPref(kWebStoreLogin,
+                            std::string() /* default_value */,
+                            false /* don't sync pref */);
 }