### Preflight Checklist

- [X] I have read the [Contributing Guidelines](https://github.com/electron/electron/blob/master/CONTRIBUTING.md) for this project.
- [X] I agree to follow the [Code of Conduct](https://github.com/electron/electron/blob/master/CODE_OF_CONDUCT.md) that this project adheres to.
- [X] I have searched the [issue tracker](https://www.github.com/electron/electron/issues) for a feature request that matches the one I want to file, without success.

### Problem Description

We need to load a custom error page when the certificate is invalid but without "isMainFrame" property we don't know when to load the custom error page using webContents.loadURL()

### Proposed Solution

webContents.on("certificate-error", ((event, url, error, certificate, callback, isMainFrame)

### Alternatives Considered

Not sure

### Additional Information

Not sure
shell/browser/api/electron_api_app.cc
Browser::LoginItemSettings val) {
    gin_helper::Dictionary dict = gin::Dictionary::CreateEmpty(isolate);
    dict.Set("openAtLogin", val.open_at_login);
    dict.Set("openAsHidden", val.open_as_hidden);
    dict.Set("restoreState", val.restore_state);
    dict.Set("wasOpenedAtLogin", val.opened_at_login);
    dict.Set("wasOpenedAsHidden", val.opened_as_hidden);
#if defined(OS_WIN)
    dict.Set("launchItems", val.launch_items);
    dict.Set("executableWillLaunchAtLogin",
             val.executable_will_launch_at_login);
#endif
    return dict.GetHandle();
  }
};
template <>
struct Converter<content::CertificateRequestResultType> {
  static bool FromV8(v8::Isolate* isolate,