Add a null check for PermissionBubbleManager::FromWebcontents.

chrome/browser/notifications/desktop_notification_service.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/desktop_notification_service.h"
 
 #include "base/bind.h"
 #include "base/metrics/histogram.h"
 #include "base/prefs/scoped_user_pref_update.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 496 matching lines @@
   // notifications is "ask", show an infobar.
   // The cache can only answer queries on the IO thread once it's initialized,
   // so don't ask the cache.
   WebContents* web_contents = WebContents::FromRenderFrameHost(
       render_frame_host);
   ContentSetting setting = GetContentSetting(origin);
   if (setting == CONTENT_SETTING_ASK) {
     if (PermissionBubbleManager::Enabled()) {
       PermissionBubbleManager* bubble_manager =
           PermissionBubbleManager::FromWebContents(web_contents);
-      bubble_manager->AddRequest(new NotificationPermissionRequest(
-          this,
-          origin,
-          DisplayNameForOriginInProcessId(
-              origin, render_frame_host->GetProcess()->GetID()),
-          callback));
+      if (bubble_manager) {
+        bubble_manager->AddRequest(new NotificationPermissionRequest(
+            this,
+            origin,
+            DisplayNameForOriginInProcessId(
+                origin, render_frame_host->GetProcess()->GetID()),
+            callback));
+      }
       return;
     }
 
     // Show an info bar requesting permission.
     InfoBarService* infobar_service =
         InfoBarService::FromWebContents(web_contents);
     // |infobar_service| may be NULL, e.g., if this request originated in a
     // browser action popup, extension background page, or any HTML that runs
     // outside of a tab.
     if (infobar_service) {
@@ skipping 215 matching lines @@
   // Tell the IO thread that this extension's permission for notifications
   // has changed.
   extensions::InfoMap* extension_info_map =
       extensions::ExtensionSystem::Get(profile_)->info_map();
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       base::Bind(&extensions::InfoMap::SetNotificationsDisabled,
                  extension_info_map, notifier_id.id, !enabled));
 #endif
 }