Add a null check for PermissionBubbleManager::FromWebcontents.

chrome/browser/media/chrome_midi_permission_context.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/media/chrome_midi_permission_context.h"
 
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
 #include "chrome/browser/content_settings/permission_queue_controller.h"
 #include "chrome/browser/content_settings/permission_request_id.h"
@@ skipping 181 matching lines @@
     case CONTENT_SETTING_BLOCK:
       PermissionDecided(id, requesting_frame, embedder, callback, false);
       break;
     case CONTENT_SETTING_ALLOW:
       PermissionDecided(id, requesting_frame, embedder, callback, true);
       break;
     default:
       if (PermissionBubbleManager::Enabled()) {
         PermissionBubbleManager* bubble_manager =
             PermissionBubbleManager::FromWebContents(web_contents);
-        bubble_manager->AddRequest(new MidiPermissionRequest(
-            this, id, requesting_frame, user_gesture,
-            profile_->GetPrefs()->GetString(prefs::kAcceptLanguages),
-            callback));
+        if (bubble_manager) {
+          bubble_manager->AddRequest(new MidiPermissionRequest(
+              this, id, requesting_frame, user_gesture,
+              profile_->GetPrefs()->GetString(prefs::kAcceptLanguages),
+              callback));
+        }
         return;
       }
 
       // TODO(gbillock): Delete this and the infobar delegate when
       // we're using only bubbles. crbug.com/337458
       GetQueueController()->CreateInfoBarRequest(
           id, requesting_frame, embedder, std::string(), base::Bind(
               &ChromeMidiPermissionContext::NotifyPermissionSet,
               base::Unretained(this), id, requesting_frame, callback));
   }
@@ skipping 39 matching lines @@
 }
 
 void ChromeMidiPermissionContext::CancelPendingInfobarRequest(
     const PermissionRequestID& id) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   if (shutting_down_)
     return;
   // TODO(gbillock): Add support for cancellation to permission bubbles.
   GetQueueController()->CancelInfoBarRequest(id);
 }