Keep the GCM data intact when the user signs out of the profile

chrome/browser/services/gcm/gcm_profile_service.cc

 // Copyright (c) 2013 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/services/gcm/gcm_profile_service.h"
 
 #include <vector>
 
 #include "base/logging.h"
 #include "base/prefs/pref_service.h"
@@ skipping 102 matching lines @@
 
   gcm_account_tracker_->Start();
 }
 
 void GCMProfileService::IdentityObserver::OnActiveAccountLogout() {
   account_id_.clear();
 
   // Check is necessary to not crash browser_tests.
   if (gcm_account_tracker_)
     gcm_account_tracker_->Stop();
-  // TODO(fgorski): If we purge here, what should happen when we get
-  // OnActiveAccountLogin() right after that?
-  driver_->Purge();
+  // When sign-in enforcement is not dropped, OnSignedOut will also clear all
+  // the GCM data and a new GCM ID will be retrieved after the user signs in
+  // again. Otherwise, the user sign-out will not affect the existing GCM
+  // data.
+  driver_->OnSignedOut();
 }
 
 std::string GCMProfileService::IdentityObserver::SignedInUserName() const {
   return driver_->IsStarted() ? account_id_ : std::string();
 }
 
 void GCMProfileService::IdentityObserver::AccountsUpdated(
     const std::vector<GCMClient::AccountTokenInfo>& account_tokens) {
   driver_->SetAccountTokens(account_tokens);
 }
@@ skipping 92 matching lines @@
   return identity_observer_ ? identity_observer_->SignedInUserName()
                             : std::string();
 #endif  // defined(OS_ANDROID)
 }
 
 void GCMProfileService::SetDriverForTesting(GCMDriver* driver) {
   driver_.reset(driver);
 }
 
 }  // namespace gcm