Fix Launcher crash in ChromeOS guest mode.

chrome/browser/ui/app_list/start_page_service.cc

 // Copyright 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/ui/app_list/start_page_service.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 68 matching lines @@
       state == SPEECH_RECOGNITION_IN_SPEECH;
 }
 
 }  // namespace
 
 class StartPageService::ProfileDestroyObserver
     : public content::NotificationObserver {
  public:
   explicit ProfileDestroyObserver(StartPageService* service)
       : service_(service) {
+    if (service_->profile()->IsOffTheRecord()) {
+      // We need to be notified when the original profile gets destroyed as well
+      // as the OTR profile, because the original profile will be destroyed
+      // first, and a DCHECK at that time ensures that the OTR profile has 0
+      // hosts. See http://crbug.com/463419.
+      registrar_.Add(
+          this, chrome::NOTIFICATION_PROFILE_DESTROYED,
+          content::Source<Profile>(service_->profile()->GetOriginalProfile()));
+    }
     registrar_.Add(this,
                    chrome::NOTIFICATION_PROFILE_DESTROYED,
                    content::Source<Profile>(service_->profile()));
   }
   ~ProfileDestroyObserver() override {}
 
  private:
   // content::NotificationObserver
   void Observe(int type,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override {
     DCHECK_EQ(chrome::NOTIFICATION_PROFILE_DESTROYED, type);
-    DCHECK_EQ(service_->profile(), content::Source<Profile>(source).ptr());
+    DCHECK(service_->profile()->IsSameProfile(
+        content::Source<Profile>(source).ptr()));
+    registrar_.RemoveAll();
     service_->Shutdown();
   }
 
   StartPageService* service_;  // Owner of this class.
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileDestroyObserver);
 };
 
 class StartPageService::StartPageWebContentsDelegate
@@ skipping 553 matching lines @@
 
   // Check for a new doodle.
   content::BrowserThread::PostDelayedTask(
       content::BrowserThread::UI, FROM_HERE,
       base::Bind(&StartPageService::FetchDoodleJson,
                  weak_factory_.GetWeakPtr()),
       recheck_delay);
 }
 
 }  // namespace app_list