Separate the syncing of extension settings and app settings into separate data

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 e51f1c14b66e5b8bf35f0ab07eee4691c457dbd9..b161ef8ac07c8c96bebf491b2376db1cdc152aea 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -1374,8 +1374,9 @@ const char kSyncKeepEverythingSynced[] = "sync.keep_everything_synced";
 const char kSyncBookmarks[] = "sync.bookmarks";
 const char kSyncPasswords[] = "sync.passwords";
 const char kSyncPreferences[] = "sync.preferences";
-const char kSyncApps[] = "sync.apps";
 const char kSyncAppNotifications[] = "sync.app_notifications";
+const char kSyncAppSettings[] = "sync.app_settings";
+const char kSyncApps[] = "sync.apps";
 const char kSyncAutofill[] = "sync.autofill";
 const char kSyncAutofillProfile[] = "sync.autofill_profile";
 const char kSyncThemes[] = "sync.themes";