Avoid creating PasswordsPrivateDelegate when shutting down.

chrome/browser/extensions/api/passwords_private/passwords_private_event_router.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/extensions/api/passwords_private/passwords_private_event_router.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 30 matching lines @@
       api::passwords_private::OnPlaintextPasswordRetrieved::kEventName);
 }
 
 PasswordsPrivateEventRouter::~PasswordsPrivateEventRouter() {}
 
 void PasswordsPrivateEventRouter::Shutdown() {
   if (event_router_)
     event_router_->UnregisterObserver(this);
 
   PasswordsPrivateDelegate* delegate =
-      PasswordsPrivateDelegateFactory::GetForBrowserContext(context_);
-  delegate->RemoveObserver(this);
+      PasswordsPrivateDelegateFactory::GetForBrowserContext(context_,
+                                                            false /* create */);
+  if (delegate)
+    delegate->RemoveObserver(this);
 }
 
 void PasswordsPrivateEventRouter::OnListenerAdded(
     const EventListenerInfo& details) {
   // Start listening to change events and propagate the original lists to
   // listeners.
   StartOrStopListeningForChanges();
   SendSavedPasswordListToListeners();
   SendPasswordExceptionListToListeners();
 }
@@ skipping 71 matching lines @@
       event_router_->HasEventListener(
           api::passwords_private::OnPasswordExceptionsListChanged::kEventName);
   bool should_listen_for_plaintext_password_retrieval =
       event_router_->HasEventListener(
           api::passwords_private::OnPlaintextPasswordRetrieved::kEventName);
   bool should_listen = should_listen_for_saved_password_changes ||
       should_listen_for_password_exception_changes ||
       should_listen_for_plaintext_password_retrieval;
 
   PasswordsPrivateDelegate* delegate =
-      PasswordsPrivateDelegateFactory::GetForBrowserContext(context_);
+      PasswordsPrivateDelegateFactory::GetForBrowserContext(context_,
+                                                            true /* create */);
   if (should_listen && !listening_)
     delegate->AddObserver(this);
   else if (!should_listen && listening_)
     delegate->RemoveObserver(this);
 
   listening_ = should_listen;
 }
 
 PasswordsPrivateEventRouter* PasswordsPrivateEventRouter::Create(
     content::BrowserContext* context) {
   return new PasswordsPrivateEventRouter(context);
 }
 
 }  // namespace extensions