Pref service: add support for tracked prefs.

services/preferences/tracked/segregated_pref_store.cc

Index: services/preferences/tracked/segregated_pref_store.cc
diff --git a/services/preferences/tracked/segregated_pref_store.cc b/services/preferences/tracked/segregated_pref_store.cc
index 8ddc5c040d1555c5e6a190c837026a92c2d22d25..4afec8f8ef3829b767017164513865450a79fb83 100644
--- a/services/preferences/tracked/segregated_pref_store.cc
+++ b/services/preferences/tracked/segregated_pref_store.cc
@@ -51,11 +51,13 @@ void SegregatedPrefStore::AggregatingObserver::OnInitializationCompleted(
 SegregatedPrefStore::SegregatedPrefStore(
     const scoped_refptr<PersistentPrefStore>& default_pref_store,
     const scoped_refptr<PersistentPrefStore>& selected_pref_store,
-    const std::set<std::string>& selected_pref_names)
+    const std::set<std::string>& selected_pref_names,
+    prefs::mojom::TrackedPreferenceValidationDelegatePtr validation_delegate)
     : default_pref_store_(default_pref_store),
       selected_pref_store_(selected_pref_store),
       selected_preference_names_(selected_pref_names),
-      aggregating_observer_(this) {
+      aggregating_observer_(this),
+      validation_delegate_(std::move(validation_delegate)) {

[gab, 2017/04/03 16:11:17]

This member is unused?

[Sam McNally, 2017/04/04 03:24:49]

It's used by the PrefHashFilters attached to the two PrefStores. They need
somewhere external to manage its lifetime. Added a comment.

   default_pref_store_->AddObserver(&aggregating_observer_);
   selected_pref_store_->AddObserver(&aggregating_observer_);
 }