Account reconcilor: Use cookie store cookie changed subscription.

chrome/browser/signin/signin_cookie_changed_subscription.cc

+// 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.
+
+#include "chrome/browser/signin/signin_cookie_changed_subscription.h"
+
+#include "content/public/browser/browser_thread.h"
+#include "net/cookies/cookie_store.h"
+#include "net/url_request/url_request_context.h"
+#include "net/url_request/url_request_context_getter.h"
+
+namespace {
+
+// Adds a callback for cookie changed events. This method is called on the IO
+// thread, so it is safe to access the cookie store.
+void RegisterForCookieChangesOnIOThread(
+    scoped_refptr<net::URLRequestContextGetter> context_getter,
+    const GURL url,
+    const std::string name,
+    const net::CookieStore::CookieChangedCallback callback,
+    SigninCookieChangedSubscription::SubscriptionHolder*
+        out_subscription_holder) {
+  DCHECK(out_subscription_holder);
+  net::CookieStore* cookie_store =
+      context_getter->GetURLRequestContext()->cookie_store();
+  DCHECK(cookie_store);
+  out_subscription_holder->subscription =
+      cookie_store->AddCallbackForCookie(url, name, callback);
+}
+
+// Posts a task on the |proxy| task runner that calls |OnCookieChanged| on
+// |subscription|.
+// Note that this method is called on the IO thread, so |subscription| must
+// not be used here, it is only passed around.
+void RunAsyncOnCookieChanged(
+    scoped_refptr<base::TaskRunner> proxy,
+    base::WeakPtr<SigninCookieChangedSubscription> subscription,
+    const net::CanonicalCookie& cookie,
+    bool removed) {
+  proxy->PostTask(FROM_HERE,
+                  base::Bind(&SigninCookieChangedSubscription::OnCookieChanged,
+                             subscription,
+                             cookie,
+                             removed));
+}
+
+}  // namespace
+
+SigninCookieChangedSubscription::SubscriptionHolder::SubscriptionHolder() {
+}
+
+SigninCookieChangedSubscription::SubscriptionHolder::~SubscriptionHolder() {
+}
+
+SigninCookieChangedSubscription::SigninCookieChangedSubscription(
+    const net::CookieStore::CookieChangedCallback& callback)
+    : callback_(callback), subscription_holder_io_(new SubscriptionHolder()) {
+}
+
+SigninCookieChangedSubscription::~SigninCookieChangedSubscription() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  content::BrowserThread::DeleteOnIOThread::Destruct(

[droger, 2014/11/04 10:31:36]

Optional:
This assumes that the network thread is the IO thread.
It would be cleaner to keep a reference to the network task runner and use it
here.

[msarda, 2014/11/04 12:06:06]

Done.

+      subscription_holder_io_.release());
+}
+
+void SigninCookieChangedSubscription::OnCookieChanged(
+    const net::CanonicalCookie& cookie,
+    bool removed) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  if (!callback_.is_null()) {
+    callback_.Run(cookie, removed);
+  }
+}
+
+void SigninCookieChangedSubscription::RegisterForCookieChangedNotifications(
+    scoped_refptr<net::URLRequestContextGetter> context_getter,
+    const GURL& url,
+    const std::string& name) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  // The cookie store can only be accessed from the context getter which lives
+  // on the IO thread. As |AddCookieChangedCallback| is called from the main
+  // thread, a thread jump is needed to register for cookie changed
+  // notifications.
+  net::CookieStore::CookieChangedCallback run_on_current_thread_callback =
+      base::Bind(&RunAsyncOnCookieChanged,
+                 base::MessageLoopProxy::current(),
+                 this->AsWeakPtr());
+  content::BrowserThread::PostTask(

[droger, 2014/11/04 10:31:36]

I think this would be better:
context_getter->GetNetworkTaskRunner()->PostTask():

[msarda, 2014/11/04 12:06:06]

Done.

+      content::BrowserThread::IO,
+      FROM_HERE,
+      base::Bind(&RegisterForCookieChangesOnIOThread,
+                 context_getter,
+                 url,
+                 name,
+                 run_on_current_thread_callback,
+                 base::Unretained(subscription_holder_io_.get())));
+}