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

chrome/utility/profile_import_handler.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 "chrome/utility/profile_import_handler.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
@@ skipping 16 matching lines @@
 // static
 void ProfileImportHandler::Create(
     mojo::InterfaceRequest<chrome::mojom::ProfileImport> request) {
   mojo::MakeStrongBinding(base::MakeUnique<ProfileImportHandler>(),
                           std::move(request));
 }
 
 void ProfileImportHandler::StartImport(
     const importer::SourceProfile& source_profile,
     uint16_t items,
-    std::unique_ptr<base::DictionaryValue> localized_strings,
+    const base::DictionaryValue& localized_strings,
     chrome::mojom::ProfileImportObserverPtr observer) {
   content::UtilityThread::Get()->EnsureBlinkInitialized();
   importer_ = importer::CreateImporterByType(source_profile.importer_type);
   if (!importer_.get()) {
     observer->OnImportFinished(false, "Importer could not be created.");
     return;
   }
 
   items_to_import_ = items;
 
   // Create worker thread in which importer runs.
   import_thread_.reset(new base::Thread("import_thread"));
 #if defined(OS_WIN)
   import_thread_->init_com_with_mta(false);
 #endif
   if (!import_thread_->Start()) {
     NOTREACHED();
     ImporterCleanup();
   }
   bridge_ = new ExternalProcessImporterBridge(
-      *localized_strings,
+      localized_strings,
       ThreadSafeProfileImportObserverPtr::Create(std::move(observer)));
   import_thread_->task_runner()->PostTask(
       FROM_HERE, base::Bind(&Importer::StartImport, importer_,
                             source_profile, items, base::RetainedRef(bridge_)));
 }
 
 void ProfileImportHandler::CancelImport() {
   ImporterCleanup();
 }
 
 void ProfileImportHandler::ReportImportItemFinished(importer::ImportItem item) {
   items_to_import_ ^= item;  // Remove finished item from mask.
   if (items_to_import_ == 0) {
     ImporterCleanup();
   }
 }
 
 void ProfileImportHandler::ImporterCleanup() {
   importer_->Cancel();
   importer_ = NULL;
   bridge_ = NULL;
   import_thread_.reset();
   content::UtilityThread::Get()->ReleaseProcessIfNeeded();
 }