### 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.

### Electron Version

13.1.7

### What operating system are you using?

Windows

### Operating System Version

Windows 10 version 20H2

### What arch are you using?

x64

### Last Known Working Electron version

12.0.15

### Expected Behavior

Checking `navigator.userAgentData` in Chrome 91 returns an array of brands appropriately. Electron 13/14 do not return anything.

This appears to then become a problem for my situation. I am posting a form with hidden variables to a third-party vendor I work with. This form post ultimately loads an iframe.

Expected: As it does in Chrome 91, load the iframe from this third-party vendor.

### Actual Behavior

A header of "sec-ch-ua" is included in the request to the third-party vendor and it is blank. They are rejecting the post because of an invalid header. I suspect this is because Chrome 13/14 does not make this hint data made available correctly.

I tried loading various sites in Chrome 91 that do load brand names in Electron 13/14 and they are empty if you review `navigator.userAgentData`.

### Testcase Gist URL

_No response_

### Additional Information

_No response_
shell/browser/electron_browser_client.cc
content::RenderFrameHost* rfh,
    content::SiteInstance* pending_site_instance) {
  
  auto* web_contents = content::WebContents::FromRenderFrameHost(rfh);
  auto* pending_process = pending_site_instance->GetProcess();
  pending_processes_[pending_process->GetID()] = web_contents;
  if (rfh->GetParent())
    renderer_is_subframe_.insert(pending_process->GetID());
  else
    renderer_is_subframe_.erase(pending_process->GetID());
}
void ElectronBrowserClient::AppendExtraCommandLineSwitches(
    base::CommandLine* command_line,
    int process_id) {
  
  {
    base::ThreadRestrictions::ScopedAllowIO allow_io;
    base::FilePath child_path;
    base::FilePath program =
        base::MakeAbsoluteFilePath(command_line->GetProgram());
#if BUILDFLAG(IS_MAC)
    auto renderer_child_path = content::ChildProcessHost::GetChildPath(
        content::ChildProcessHost::CHILD_RENDERER);
    auto gpu_child_path = content::ChildProcessHost::GetChildPath(
        content::ChildProcessHost::CHILD_GPU);
#if BUILDFLAG(ENABLE_PLUGINS)
    auto plugin_child_path = content::ChildProcessHost::GetChildPath(
        content::ChildProcessHost::CHILD_PLUGIN);
#endif
    if (program != renderer_child_path && program != gpu_child_path