Delete the PreferenceMACs on profile deletion.

services/preferences/public/cpp/persistent_pref_store_client.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 "base/values.h"
 #include "components/prefs/pref_registry.h"
 #include "mojo/common/values.mojom.h"
 #include "mojo/common/values_struct_traits.h"
@@ skipping 163 matching lines @@
 void PersistentPrefStoreClient::SchedulePendingLossyWrites() {
   DCHECK(pref_store_);
   return pref_store_->SchedulePendingLossyWrites();
 }
 
 void PersistentPrefStoreClient::ClearMutableValues() {
   DCHECK(pref_store_);
   return pref_store_->ClearMutableValues();
 }
 
+void PersistentPrefStoreClient::OnStoreDeletionFromDisk() {
+  DCHECK(pref_store_);
+  return pref_store_->OnStoreDeletionFromDisk();
+}
+
 PersistentPrefStoreClient::~PersistentPrefStoreClient() {
   if (!pref_store_)
     return;
 
   CommitPendingWrite();
 }
 
 void PersistentPrefStoreClient::OnConnect(
     mojom::PersistentPrefStoreConnectionPtr connection,
     mojom::PersistentPrefStoreConnectionPtr incognito_connection,
@@ skipping 67 matching lines @@
       update_value->set_atomic_update(nullptr);
     }
     updates.emplace_back(base::in_place, pref.first, std::move(update_value),
                          pref.second.second);
   }
   pref_store_->SetValues(std::move(updates));
   pending_writes_.clear();
 }
 
 }  // namespace prefs