[Extensions][TaskScheduler] Update ActivityLog for scheduling migration

chrome/browser/extensions/activity_log/activity_log_task_runner.h

Index: chrome/browser/extensions/activity_log/activity_log_task_runner.h
diff --git a/chrome/browser/extensions/activity_log/activity_log_task_runner.h b/chrome/browser/extensions/activity_log/activity_log_task_runner.h
new file mode 100644
index 0000000000000000000000000000000000000000..1a699216d5ccab229021fb7c5664ad4a49c7c55a
--- /dev/null
+++ b/chrome/browser/extensions/activity_log/activity_log_task_runner.h
@@ -0,0 +1,20 @@
+// 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.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_ACTIVITY_LOG_ACTIVITY_LOG_TASK_RUNNER_H_
+#define CHROME_BROWSER_EXTENSIONS_ACTIVITY_LOG_ACTIVITY_LOG_TASK_RUNNER_H_
+
+#include "base/memory/ref_counted.h"
+
+namespace base {
+class TaskRunner;
+}
+
+namespace extensions {
+
+const scoped_refptr<base::TaskRunner> GetActivityLogTaskRunner();
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_ACTIVITY_LOG_ACTIVITY_LOG_TASK_RUNNER_H_