Use UtilityProcessHost to patch files.

chrome/browser/component_updater/test/component_patcher_unittest.h

 // Copyright 2013 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.
 
 #ifndef CHROME_BROWSER_COMPONENT_UPDATER_TEST_COMPONENT_PATCHER_UNITTEST_H_
 #define CHROME_BROWSER_COMPONENT_UPDATER_TEST_COMPONENT_PATCHER_UNITTEST_H_
 
 #include "base/files/file_path.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/common/chrome_paths.h"
+#include "content/public/test/test_browser_thread_bundle.h"
 #include "courgette/courgette.h"
 #include "courgette/third_party/bsdiff.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace component_updater {
 
 class MockComponentPatcher;
 class ReadOnlyTestInstaller;
 
 const char binary_output_hash[] =
     "599aba6d15a7da390621ef1bacb66601ed6aed04dadc1f9b445dcfe31296142a";
 
 // These constants are duplicated from chrome/installer/util/util_constants.h,
 // to avoid introducing a dependency from the unit tests to the installer.
 const int kCourgetteErrorOffset = 300;
 const int kBsdiffErrorOffset = 600;
 
 class ComponentPatcherOperationTest : public testing::Test {
  public:
   explicit ComponentPatcherOperationTest();
   virtual ~ComponentPatcherOperationTest();
 
  protected:
   base::ScopedTempDir input_dir_;
   base::ScopedTempDir installed_dir_;
   base::ScopedTempDir unpack_dir_;
-  scoped_ptr<MockComponentPatcher> patcher_;
   scoped_ptr<ReadOnlyTestInstaller> installer_;
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
+
+ private:
+  content::TestBrowserThreadBundle thread_bundle_;
 };
 
 }  // namespace component_updater
 
 #endif  // CHROME_BROWSER_COMPONENT_UPDATER_TEST_COMPONENT_PATCHER_UNITTEST_H_