Fix crash when affiliated invalidation service becomes available

chrome/browser/chromeos/policy/affiliated_invalidation_service_provider_impl.cc

 // Copyright 2015 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/chromeos/policy/affiliated_invalidation_service_provider_impl.h"
 
 #include <vector>
 
 #include "base/logging.h"
 #include "chrome/browser/browser_process.h"
@@ skipping 224 matching lines @@
   }
 
   if (!device_invalidation_service_) {
     // The lack of a device-global invalidation service implies that another
     // connected invalidation service is being made available to consumers
     // already. There is no need to switch from that to the service which just
     // connected.
     return;
   }
 
-  if (invalidation_service != device_invalidation_service_.get()) {
-    // If an invalidation service other than the device-global one connected,
-    // destroy the device-global service.
-    invalidation_service_ = nullptr;
+  // Make the invalidation service that just connected available to consumers.
+  invalidation_service_ = nullptr;
+  SetInvalidationService(invalidation_service);
+
+  if (invalidation_service_ &&
+      device_invalidation_service_ &&
+      invalidation_service_ != device_invalidation_service_.get()) {
+    // If a different invalidation service is being made available to consumers
+    // now, destroy the device-global one.
     DestroyDeviceInvalidationService();
   }
 
-  // Make the invalidation service that just connected available to consumers.
-  SetInvalidationService(invalidation_service);
 }
 
 void
 AffiliatedInvalidationServiceProviderImpl::OnInvalidationServiceDisconnected(
     invalidation::InvalidationService* invalidation_service) {
   DCHECK(!is_shut_down_);
 
   if (invalidation_service != invalidation_service_) {
     // If the invalidation service which disconnected was not being made
     // available to consumers, return.
@@ skipping 72 matching lines @@
                     OnInvalidationServiceSet(invalidation_service_));
 }
 
 void
 AffiliatedInvalidationServiceProviderImpl::DestroyDeviceInvalidationService() {
   device_invalidation_service_observer_.reset();
   device_invalidation_service_.reset();
 }
 
 }  // namespace policy