Allow script to request durable storage permission (chrome side)

chrome/browser/permissions/permission_manager.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/permissions/permission_manager.h"
 
 #include "base/callback.h"
 #include "chrome/browser/permissions/permission_context.h"
 #include "chrome/browser/permissions/permission_context_base.h"
 #include "chrome/browser/permissions/permission_request_id.h"
@@ skipping 40 matching lines @@
       return CONTENT_SETTINGS_TYPE_NOTIFICATIONS;
     case PermissionType::GEOLOCATION:
       return CONTENT_SETTINGS_TYPE_GEOLOCATION;
     case PermissionType::PROTECTED_MEDIA_IDENTIFIER:
 #if defined(OS_ANDROID) || defined(OS_CHROMEOS)
       return CONTENT_SETTINGS_TYPE_PROTECTED_MEDIA_IDENTIFIER;
 #else
       NOTIMPLEMENTED();
       break;
 #endif
+    case PermissionType::DURABLE_STORAGE:
+      return CONTENT_SETTINGS_TYPE_DURABLE_STORAGE;
     case PermissionType::NUM:
       // This will hit the NOTREACHED below.
       break;
   }
 
   NOTREACHED() << "Unknown content setting for permission "
                << static_cast<int>(permission);
   return CONTENT_SETTINGS_TYPE_DEFAULT;
 }
 
@@ skipping 166 matching lines @@
     // Add the callback to |callbacks| which will be run after the loop to
     // prevent re-entrance issues.
     callbacks.push_back(
         base::Bind(subscription->callback,
                    ContentSettingToPermissionStatus(new_value)));
   }
 
   for (const auto& callback : callbacks)
     callback.Run();
 }