[Sync] Add priority preferences datatype for mobile

chrome/browser/sync/profile_sync_service.cc

Index: chrome/browser/sync/profile_sync_service.cc
diff --git a/chrome/browser/sync/profile_sync_service.cc b/chrome/browser/sync/profile_sync_service.cc
index 1cec63d87200ff9702d39e8fee97d3bfdc3170fb..f47657774b4ab6a75b1af24619c1fb10de963653 100644
--- a/chrome/browser/sync/profile_sync_service.cc
+++ b/chrome/browser/sync/profile_sync_service.cc
@@ -1783,10 +1783,8 @@ void ProfileSyncService::ChangePreferredDataTypes(
 
   DVLOG(1) << "ChangePreferredDataTypes invoked";
   const syncer::ModelTypeSet registered_types = GetRegisteredDataTypes();
-  const syncer::ModelTypeSet registered_preferred_types =
-      Intersection(registered_types, preferred_types);
-  sync_prefs_.SetPreferredDataTypes(registered_types,
-                                    registered_preferred_types);
+  // Will only enable those types that are registered and preferred.
+  sync_prefs_.SetPreferredDataTypes(registered_types, preferred_types);
 
   // Now reconfigure the DTM.
   ReconfigureDatatypeManager();