Integrate registry_hash_store_contents with the rest of tracked prefs.

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 57 matching lines @@
 class InterceptingPrefFilter : public PrefFilter {
  public:
   InterceptingPrefFilter();
   ~InterceptingPrefFilter() override;
 
   // 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 {}
-  void FilterSerializeData(
-      base::DictionaryValue* pref_store_contents) override {}
+  base::Callback<void(bool)> FilterSerializeData(
+      base::DictionaryValue* pref_store_contents) override {
+    return base::Callback<void(bool)>();
+  }
 
   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 862 matching lines @@
   ASSERT_TRUE(file_writer->HasPendingWrite());
 
   // Call CommitPendingWrite and check that the lossy pref is there with the
   // last value set above.
   pref_store->CommitPendingWrite();
   ASSERT_FALSE(file_writer->HasPendingWrite());
   ASSERT_EQ("{\"lossy\":\"lossy\"}", GetTestFileContents());
 }
 
 }  // namespace base