Delete the PreferenceMACs on profile deletion.

services/preferences/public/cpp/tests/persistent_pref_store_client_unittest.cc

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "services/preferences/public/cpp/persistent_pref_store_client.h"
 
 #include <utility>
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
@@ skipping 75 matching lines @@
  private:
   void SetValues(std::vector<mojom::PrefUpdatePtr> updates) override {
     last_updates_ = std::move(updates);
     if (on_update_)
       std::move(on_update_).Run();
   }
 
   void CommitPendingWrite() override {}
   void SchedulePendingLossyWrites() override {}
   void ClearMutableValues() override {}
+  void CleanupForProfileDeletion() override {}
 
   base::MessageLoop message_loop_;
 
   std::unique_ptr<PrefService> pref_service_;
 
   mojo::Binding<mojom::PersistentPrefStore> binding_;
 
   std::vector<mojom::PrefUpdatePtr> last_updates_;
   base::OnceClosure on_update_;
 
@@ skipping 387 matching lines @@
   }
   auto update = WaitForUpdate();
   ASSERT_TRUE(update->is_atomic_update());
   base::DictionaryValue expected_value;
   expected_value.SetInteger("path.to.integer", 1);
   EXPECT_EQ(expected_value, *update->get_atomic_update());
 }
 
 }  // namespace
 }  // namespace prefs