gecko-dev/toolkit/components/extensions/ext-c-permissions.js

"use strict";

var {
  ExtensionError,
} = ExtensionUtils;

this.permissions = class extends ExtensionAPI {
  getAPI(context) {
    return {
      permissions: {
        async request(perms) {
          let winUtils = context.contentWindow.getInterface(Ci.nsIDOMWindowUtils);
          if (!winUtils.isHandlingUserInput) {
            throw new ExtensionError("May only request permissions from a user input handler");
          }

          return context.childManager.callParentAsyncFunction("permissions.request_parent", [perms]);
        },
      },
    };
  }
};