Reland of Moving previews code from components/ to chrome/

components/previews/core/previews_ui_service_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 "components/previews/core/previews_ui_service.h"
 
 #include <memory>
 
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
 #include "components/previews/core/previews_io_data.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace previews {
 
 namespace {
 
 class TestPreviewsUIService : public PreviewsUIService {
  public:
   TestPreviewsUIService(
       PreviewsIOData* previews_io_data,
       const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
       std::unique_ptr<PreviewsOptOutStore> previews_opt_out_store)
       : PreviewsUIService(previews_io_data,
                           io_task_runner,
-                          std::move(previews_opt_out_store)),
+                          std::move(previews_opt_out_store),
+                          PreviewsIsEnabledCallback()),
         io_data_set_(false) {}
   ~TestPreviewsUIService() override {}
 
   // Set |io_data_set_| to true and use base class functionality.
   void SetIOData(base::WeakPtr<PreviewsIOData> previews_io_data) override {
     io_data_set_ = true;
     PreviewsUIService::SetIOData(previews_io_data);
   }
 
   // Whether SetIOData was called.
@@ skipping 38 matching lines @@
       new PreviewsIOData(loop_.task_runner(), loop_.task_runner())));
   set_ui_service(base::WrapUnique(
       new TestPreviewsUIService(io_data(), loop_.task_runner(), nullptr)));
   base::RunLoop().RunUntilIdle();
   // After the outstanding posted tasks have run, SetIOData should have been
   // called for |ui_service_|.
   EXPECT_TRUE(ui_service()->io_data_set());
 }
 
 }  // namespace previews