Properly handle disabling sync via the google dashboard.

chrome/browser/sync/profile_sync_service.cc

 // 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.
 
 #include "chrome/browser/sync/profile_sync_service.h"
 
 #include <cstddef>
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 966 matching lines @@
   const GoogleServiceAuthError auth_error =
       ConnectionStatusToAuthError(status);
   DVLOG(1) << "Connection status change: " << auth_error.ToString();
   UpdateAuthErrorState(auth_error);
 }
 
 void ProfileSyncService::OnStopSyncingPermanently() {
   UpdateAuthErrorState(AuthError(AuthError::SERVICE_UNAVAILABLE));
   sync_prefs_.SetStartSuppressed(true);
   DisableForUser();
+  // If signout is allowed, signout the user on a dashboard clear.
+  if (!auto_start_enabled_)  // Skip signout on ChromeOS/Android.
+    signin_->SignOut();
 }
 
 void ProfileSyncService::OnPassphraseRequired(
     syncer::PassphraseRequiredReason reason,
     const sync_pb::EncryptedData& pending_keys) {
   DCHECK(backend_.get());
   DCHECK(backend_->IsNigoriEnabled());
 
   // TODO(lipalani) : add this check to other locations as well.
   if (HasUnrecoverableError()) {
@@ skipping 977 matching lines @@
   // See http://stackoverflow.com/questions/6224121/is-new-this-myclass-undefined-behaviour-after-directly-calling-the-destru.
   ProfileSyncService* old_this = this;
   this->~ProfileSyncService();
   new(old_this) ProfileSyncService(
       new ProfileSyncComponentsFactoryImpl(profile,
                                            CommandLine::ForCurrentProcess()),
       profile,
       signin,
       behavior);
 }