Unconditionally delete the unpack path in the UpdateClient.

components/update_client/component.cc

 // Copyright 2017 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/update_client/component.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 77 matching lines @@
 
 void InstallOnBlockingTaskRunner(
     const scoped_refptr<base::SingleThreadTaskRunner>& main_task_runner,
     const scoped_refptr<base::SequencedTaskRunner>& blocking_task_runner,
     const base::FilePath& unpack_path,
     const std::string& fingerprint,
     const scoped_refptr<CrxInstaller>& installer,
     InstallOnBlockingTaskRunnerCompleteCallback callback) {
   DCHECK(blocking_task_runner->RunsTasksOnCurrentThread());
 
+  DCHECK(base::DirectoryExists(unpack_path));
   const auto result = DoInstallOnBlockingTaskRunner(
       main_task_runner, blocking_task_runner, unpack_path, fingerprint,
       installer, callback);
+  base::DeleteFile(unpack_path, true);
 
   const ErrorCategory error_category =
       result.error ? ErrorCategory::kInstallError : ErrorCategory::kErrorNone;
   main_task_runner->PostTask(
       FROM_HERE,
       base::Bind(callback, static_cast<int>(error_category),
                  static_cast<int>(result.error), result.extended_error));
 }
 
 void UnpackCompleteOnBlockingTaskRunner(
@@ skipping 594 matching lines @@
 void Component::StateUninstalled::DoHandle() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   auto& component = State::component();
   component.AppendEvent(BuildUninstalledEventElement(component));
 
   TransitionState(nullptr);
 }
 
 }  // namespace update_client