Account reconcilor: Use cookie store cookie changed subscription.

chrome/browser/signin/signin_cookie_changed_subscription.h

+// Copyright 2014 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_SIGNIN_SIGNIN_COOKIE_CHANGED_SUBSCRIPTION_H_
+#define CHROME_BROWSER_SIGNIN_SIGNIN_COOKIE_CHANGED_SUBSCRIPTION_H_
+
+#include "base/memory/weak_ptr.h"
+#include "base/threading/thread_checker.h"
+#include "components/signin/core/browser/signin_client.h"
+
+
+// The subscription for a cookie changed events. This class lives on the
+// main thread.
+class SigninCookieChangedSubscription
+    : public SigninClient::CookieChangedSubscription,
+      public base::SupportsWeakPtr<SigninCookieChangedSubscription> {

[droger, 2014/10/31 12:42:01]

Maybe add a comment saying that this class must only be used from SigninClient
(and maybe this could be enforced by DEPS, if we are very paranoid). This way
you don't have to worry about exposing implementation details (such as
SupportsWeakPtr).

[msarda, 2014/10/31 13:18:40]

Is that really so important that this class supports weak pointer and that this
is visible to the users?

[droger, 2014/10/31 13:56:08]

No I think it is fine, especially since you pass a
SigninClient::CookieChangedSubscription to the user, and not this type.

+ public:
+  SigninCookieChangedSubscription(
+      const net::CookieStore::CookieChangedCallback& callback);

[droger, 2014/10/31 12:42:01]

explicit.

[msarda, 2014/10/31 13:18:40]

Done.

+  virtual ~SigninCookieChangedSubscription();

[droger, 2014/10/31 12:42:01]

s/virtual/override/

or maybe even better:
s/virtual/final/
I'm not very familiar with final though, so not sure.

[msarda, 2014/10/31 13:18:40]

I used override instead of virtual

+
+  // Sets |subscription|.
+  void SetCookieChangedSubscription(
+      scoped_ptr<net::CookieStore::CookieChangedSubscription> subscription);
+
+  // Handler for cookie changed events.
+  void OnCookieChanged(const net::CanonicalCookie& cookie, bool removed);
+
+  // Registers for cookie changed events.
+  void RegisterForCookieChangedNotifications(
+      scoped_refptr<net::URLRequestContextGetter> context_getter,
+      const GURL& url,
+      const std::string& name);
+
+ private:
+  // Callback to be run on cookie changed events.
+  net::CookieStore::CookieChangedCallback callback_;
+
+  // The cookie changed subscription on the cookie store.
+  scoped_ptr<net::CookieStore::CookieChangedSubscription>
+      cookie_changed_subscription_;
+
+  base::ThreadChecker thread_checker_;
+
+  DISALLOW_COPY_AND_ASSIGN(SigninCookieChangedSubscription);
+};
+
+#endif  // CHROME_BROWSER_SIGNIN_SIGNIN_COOKIE_CHANGED_SUBSCRIPTION_H_