Add struct traits for base::Value.

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

 // Copyright 2016 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/pref_observer_store.h"
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
@@ skipping 17 matching lines @@
 
   bool add_observer_called() { return add_observer_called_; }
   const std::set<std::string>& last_preference_set() {
     return last_preference_set_;
   }
   bool set_preferences_called() { return set_preferences_called_; }
 
   // prefs::mojom::TestPreferenceManager:
   void AddObserver(const std::vector<std::string>& preferences,
                    prefs::mojom::PreferencesObserverPtr client) override;
-  void SetPreferences(const base::DictionaryValue& preferences) override;
+  void SetPreferences(
+      std::unique_ptr<base::DictionaryValue> preferences) override;
 
  private:
   bool add_observer_called_;
   std::set<std::string> last_preference_set_;
   bool set_preferences_called_;
   mojo::Binding<PreferencesManager> binding_;
 
   DISALLOW_COPY_AND_ASSIGN(TestPreferenceManager);
 };
 
 void TestPreferenceManager::AddObserver(
     const std::vector<std::string>& preferences,
     prefs::mojom::PreferencesObserverPtr client) {
   add_observer_called_ = true;
   last_preference_set_.clear();
   last_preference_set_.insert(preferences.begin(), preferences.end());
 }
 
 void TestPreferenceManager::SetPreferences(
-    const base::DictionaryValue& preferences) {
+    std::unique_ptr<base::DictionaryValue> preferences) {
   set_preferences_called_ = true;
 }
 
 }  // namespace
 
 class PrefObserverStoreTest : public testing::Test {
  public:
   PrefObserverStoreTest() {}
   ~PrefObserverStoreTest() override {}
 
   TestPreferenceManager* manager() { return manager_.get(); }
   PrefStoreObserverMock* observer() { return &observer_; }
   PrefObserverStore* store() { return store_.get(); }
 
   bool Initialized() { return store_->initialized_; }
   void OnPreferencesChanged(const base::DictionaryValue& preferences) {
-    store_->OnPreferencesChanged(std::move(preferences));
+    store_->OnPreferencesChanged(preferences.CreateDeepCopy());
   }
 
   // testing::Test:
   void SetUp() override;
   void TearDown() override;
 
  private:
   scoped_refptr<PrefObserverStore> store_;
   prefs::mojom::PreferencesManagerPtr proxy_;
   std::unique_ptr<TestPreferenceManager> manager_;
@@ skipping 240 matching lines @@
                       observer()->changed_keys.end(), key2));
 
   observer()->changed_keys.clear();
   const int kValue3 = 9001;
   base::FundamentalValue pref3(kValue3);
   store()->SetValue(key1, pref3.CreateDeepCopy(), 0);
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(1u, observer()->changed_keys.size());
   EXPECT_TRUE(manager()->set_preferences_called());
 }