Switch base::Value typemapping to be by value instead of by unique_ptr.

extensions/utility/utility_handler.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 "extensions/utility/utility_handler.h"
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "content/public/utility/utility_thread.h"
 #include "extensions/common/constants.h"
@@ skipping 45 matching lines @@
               const UnpackCallback& callback) override {
     CHECK_GT(location, Manifest::INVALID_LOCATION);
     CHECK_LT(location, Manifest::NUM_LOCATIONS);
     DCHECK(ExtensionsClient::Get());
 
     content::UtilityThread::Get()->EnsureBlinkInitialized();
 
     Unpacker unpacker(path.DirName(), path, extension_id, location,
                       creation_flags);
     if (unpacker.Run()) {
-      callback.Run(base::string16(), unpacker.TakeParsedManifest());
+      callback.Run(base::string16(), std::move(*unpacker.TakeParsedManifest()));
     } else {
-      callback.Run(unpacker.error_message(), nullptr);
+      callback.Run(unpacker.error_message(), base::nullopt);
     }
   }
 
   static bool UnzipFileManifestIntoPath(
       const base::FilePath& file,
       const base::FilePath& path,
       std::unique_ptr<base::DictionaryValue>* manifest) {
     if (zip::UnzipWithFilterCallback(
             file, path, base::Bind(&Unpacker::IsManifestFile), false)) {
       std::string error;
@@ skipping 62 matching lines @@
   if (running_elevated)
     return;
 
   registry->AddInterface(base::Bind(&ExtensionUnpackerImpl::Create));
   registry->AddInterface(base::Bind(&ManifestParserImpl::Create));
 }
 
 }  // namespace utility_handler
 
 }  // namespace extensions