Convert JsonWriter::Write to taking a const ref for the in-param

chrome/browser/component_updater/supervised_user_whitelist_installer_unittest.cc

 // Copyright 2014 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 "base/bind.h"
 #include "base/callback.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/json/json_file_value_serializer.h"
@@ skipping 33 matching lines @@
 const char kWhitelistFile[] = "whitelist.json";
 
 std::string CrxIdToHashToCrxId(const std::string& kCrxId) {
   CrxComponent component;
   component.pk_hash =
       SupervisedUserWhitelistInstaller::GetHashFromCrxId(kCrxId);
   EXPECT_EQ(16u, component.pk_hash.size());
   return GetCrxComponentID(component);
 }
 
-std::string JsonToString(const base::DictionaryValue* dict) {
+std::string JsonToString(const base::DictionaryValue& dict) {
   std::string json;
   base::JSONWriter::Write(dict, &json);
   return json;
 }
 
 class MockComponentUpdateService : public ComponentUpdateService,
                                    public OnDemandUpdater {
  public:
   MockComponentUpdateService(
       const scoped_refptr<base::SequencedTaskRunner>& task_runner)
@@ skipping 238 matching lines @@
       component_update_service_.registered_component();
   ASSERT_TRUE(component);
   ASSERT_TRUE(component->installer->Install(manifest_, unpacked_path));
   observer.Wait();
   EXPECT_EQ(whitelist_path_.value(), observer.whitelist_path().value());
 
   std::string whitelist_contents;
   ASSERT_TRUE(base::ReadFileToString(whitelist_path_, &whitelist_contents));
   EXPECT_EQ(kWhitelistContents, whitelist_contents);
 
-  EXPECT_EQ(JsonToString(&pref_),
-            JsonToString(local_state_.GetDictionary(
+  EXPECT_EQ(JsonToString(pref_),
+            JsonToString(*local_state_.GetDictionary(
                 prefs::kRegisteredSupervisedUserWhitelists)));
 }
 
 TEST_F(SupervisedUserWhitelistInstallerTest,
        RegisterAndUninstallExistingWhitelist) {
   ASSERT_TRUE(base::CreateDirectory(whitelist_version_directory_));
   ASSERT_NO_FATAL_FAILURE(
       PrepareWhitelistDirectory(whitelist_version_directory_));
 
   // Create another whitelist directory, with an ID that is not registered.
@@ skipping 35 matching lines @@
   {
     base::RunLoop run_loop;
     installer_->UnregisterWhitelist(kOtherClientId, kCrxId);
     run_loop.RunUntilIdle();
   }
   EXPECT_FALSE(component_update_service_.registered_component());
   EXPECT_FALSE(base::DirectoryExists(whitelist_directory_));
 }
 
 }  // namespace component_updater