Fixes possible crashes for ProfileNotification is not found.

chrome/browser/notifications/message_center_notification_manager.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/notifications/message_center_notification_manager.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ skipping 146 matching lines @@
   return false;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // MessageCenter::Delegate
 
 void MessageCenterNotificationManager::DisableExtension(
     const std::string& notification_id) {
   ProfileNotification* profile_notification =
       FindProfileNotification(notification_id);
+  if (!profile_notification)
+    return;
+
   std::string extension_id = profile_notification->GetExtensionId();
   DCHECK(!extension_id.empty());  // or UI should not have enabled the command.
   DesktopNotificationService* service =
       DesktopNotificationServiceFactory::GetForProfile(
           profile_notification->profile());
   service->SetExtensionEnabled(extension_id, false);
 }
 
 void MessageCenterNotificationManager::DisableNotificationsFromSource(
     const std::string& notification_id) {
   ProfileNotification* profile_notification =
       FindProfileNotification(notification_id);
+  if (!profile_notification)
+    return;
+
   // UI should not have enabled the command if there is no valid source.
   DCHECK(profile_notification->notification().origin_url().is_valid());
   DesktopNotificationService* service =
       DesktopNotificationServiceFactory::GetForProfile(
           profile_notification->profile());
   service->DenyPermission(profile_notification->notification().origin_url());
 }
 
 void MessageCenterNotificationManager::ShowSettings(
     const std::string& notification_id) {
   // The per-message-center Settings button passes an empty string.
   if (notification_id.empty()) {
     NOTIMPLEMENTED();
     return;
   }
 
   ProfileNotification* profile_notification =
       FindProfileNotification(notification_id);
+  if (!profile_notification)
+    return;
+
   Browser* browser =
       chrome::FindOrCreateTabbedBrowser(profile_notification->profile(),
                                         chrome::HOST_DESKTOP_TYPE_NATIVE);
   if (profile_notification->GetExtensionId().empty())
     chrome::ShowContentSettings(browser, CONTENT_SETTINGS_TYPE_NOTIFICATIONS);
   else
     chrome::ShowExtensions(browser, std::string());
 }
 
 void MessageCenterNotificationManager::ShowSettingsDialog(
@@ skipping 10 matching lines @@
   // directly to MessageCenter, but this method will be called for the removals
   // of such notifications.
   NotificationMap::const_iterator iter =
       profile_notifications_.find(notification_id);
   if (iter != profile_notifications_.end())
     RemoveProfileNotification(iter->second, by_user);
 }
 
 void MessageCenterNotificationManager::OnNotificationClicked(
     const std::string& notification_id) {
-  FindProfileNotification(notification_id)->notification().Click();
+  ProfileNotification* profile_notification =
+      FindProfileNotification(notification_id);
+  if (!profile_notification)
+    return;
+  profile_notification->notification().Click();
 }
 void MessageCenterNotificationManager::OnNotificationButtonClicked(
     const std::string& notification_id,
     int button_index) {
-  FindProfileNotification(notification_id)->notification().ButtonClick(
-      button_index);
+  ProfileNotification* profile_notification =
+      FindProfileNotification(notification_id);
+  if (!profile_notification)
+    return;
+  profile_notification->notification().ButtonClick(button_index);
 }
 
 
 ////////////////////////////////////////////////////////////////////////////////
 // ImageDownloads
 
 MessageCenterNotificationManager::ImageDownloads::ImageDownloads(
     message_center::MessageCenter* message_center)
     : message_center_(message_center) {
 }
@@ skipping 158 matching lines @@
   profile_notification->notification().Close(by_user);
   std::string id = profile_notification->notification().notification_id();
   profile_notifications_.erase(id);
   delete profile_notification;
 }
 
 MessageCenterNotificationManager::ProfileNotification*
     MessageCenterNotificationManager::FindProfileNotification(
         const std::string& id) const {
   NotificationMap::const_iterator iter = profile_notifications_.find(id);
-  // If the notification is shown in UI, it must be in the map.
-  DCHECK(iter != profile_notifications_.end());
-  DCHECK((*iter).second);
+  if (iter == profile_notifications_.end())
+    return NULL;
+
   return (*iter).second;
 }