fix: register accelerator if role has no registerAccelerator (backport: 4-0-x) (#16314)

* fix: register accelerator if role has no registerAccelerator

* ensure roles[role].registerAccelerator is defined

lib/browser/api/menu-item-roles.js

@@ -248,7 +248,8 @@ exports.getDefaultAccelerator = (role) => {
 }
 
 exports.shouldRegisterAccelerator = (role) => {
-  return roles.hasOwnProperty(role) ? roles[role].registerAccelerator : true
+  const hasRoleRegister = roles.hasOwnProperty(role) && roles[role].registerAccelerator !== undefined
+  return hasRoleRegister ? roles[role].registerAccelerator : true
 }
 
 exports.getDefaultSubmenu = (role) => {