Delete the PreferenceMACs on profile deletion.

components/prefs/json_pref_store_unittest.cc

 // Copyright (c) 2012 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 "components/prefs/json_pref_store.h"
 
 #include <stdint.h>
 
 #include <memory>
 #include <utility>
@@ skipping 64 matching lines @@
 
   // PrefFilter implementation:
   void FilterOnLoad(
       const PostFilterOnLoadCallback& post_filter_on_load_callback,
       std::unique_ptr<base::DictionaryValue> pref_store_contents) override;
   void FilterUpdate(const std::string& path) override {}
   OnWriteCallbackPair FilterSerializeData(
       base::DictionaryValue* pref_store_contents) override {
     return on_write_callback_pair_;
   }
+  void OnStoreDeletionFromDisk() override {}
 
   bool has_intercepted_prefs() const { return intercepted_prefs_ != NULL; }
 
   // Finalize an intercepted read, handing |intercepted_prefs_| back to its
   // JsonPrefStore.
   void ReleasePrefs();
 
  private:
   PostFilterOnLoadCallback post_filter_on_load_callback_;
   std::unique_ptr<base::DictionaryValue> intercepted_prefs_;
@@ skipping 985 matching lines @@
     file_writer->WriteNow(MakeUnique<std::string>("foo"));
   }
   scoped_task_environment_.RunUntilIdle();
   EXPECT_FALSE(successful_write_reply_observer_.GetAndResetObservationState());
   EXPECT_TRUE(write_callback_observer_.GetAndResetPreWriteObservationState());
   EXPECT_EQ(CALLED_WITH_SUCCESS,
             write_callback_observer_.GetAndResetPostWriteObservationState());
 }
 
 }  // namespace base