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diff --git a/components/browser_context_keyed_service/refcounted_browser_context_keyed_service.h b/components/browser_context_keyed_service/refcounted_browser_context_keyed_service.h
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+// 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.
+
+#ifndef COMPONENTS_BROWSER_CONTEXT_KEYED_SERVICE_REFCOUNTED_BROWSER_CONTEXT_KEYED_SERVICE_H_
+#define COMPONENTS_BROWSER_CONTEXT_KEYED_SERVICE_REFCOUNTED_BROWSER_CONTEXT_KEYED_SERVICE_H_
+
+#include "base/memory/ref_counted.h"
+#include "base/sequenced_task_runner_helpers.h"
+#include "content/public/browser/browser_thread.h"
+
+class RefcountedProfileKeyedService;
+
+namespace impl {
+
+struct RefcountedProfileKeyedServiceTraits {
+  static void Destruct(const RefcountedProfileKeyedService* obj);
+};
+
+}  // namespace impl
+
+// Base class for refcounted objects that hang off the Profile.
+//
+// The two pass shutdown described in ProfileKeyedService works a bit
+// differently because there could be outstanding references on other
+// threads. ShutdownOnUIThread() will be called on the UI thread, and then the
+// destructor will run when the last reference is dropped, which may or may not
+// be after the corresponding Profile has been destroyed.
+//
+// Optionally, if you initialize your service with the constructor that takes a
+// thread ID, your service will be deleted on that thread. We can't use
+// content::DeleteOnThread<> directly because RefcountedProfileKeyedService
+// must be one type that RefcountedProfileKeyedServiceFactory can use.
+class RefcountedProfileKeyedService
+    : public base::RefCountedThreadSafe<
+          RefcountedProfileKeyedService,
+          impl::RefcountedProfileKeyedServiceTraits> {
+ public:
+  // Unlike ProfileKeyedService, ShutdownOnUI is not optional. You must do
+  // something to drop references during the first pass Shutdown() because this
+  // is the only point where you are guaranteed that something is running on
+  // the UI thread. The PKSF framework will ensure that this is only called on
+  // the UI thread; you do not need to check for that yourself.
+  virtual void ShutdownOnUIThread() = 0;
+
+ protected:
+  // If your service does not need to be deleted on a specific thread, use the
+  // default constructor.
+  RefcountedProfileKeyedService();
+
+  // If you need your service to be deleted on a specific thread (for example,
+  // you're converting a service that used content::DeleteOnThread<IO>), then
+  // use this constructor with the ID of the thread.
+  explicit RefcountedProfileKeyedService(
+      const content::BrowserThread::ID thread_id);
+
+  // The second pass destruction can happen anywhere unless you specify which
+  // thread this service must be destroyed on by using the second constructor.
+  virtual ~RefcountedProfileKeyedService();
+
+ private:
+  friend struct impl::RefcountedProfileKeyedServiceTraits;
+  friend class base::DeleteHelper<RefcountedProfileKeyedService>;
+
+  // Do we have to delete this object on a specific thread?
+  bool requires_destruction_on_thread_;
+  content::BrowserThread::ID thread_id_;
+};
+
+#endif  // COMPONENTS_BROWSER_CONTEXT_KEYED_SERVICE_REFCOUNTED_BROWSER_CONTEXT_KEYED_SERVICE_H_