### Preflight Checklist

- [X] I have read the [Contributing Guidelines](https://github.com/electron/electron/blob/main/CONTRIBUTING.md) for this project.
- [X] I agree to follow the [Code of Conduct](https://github.com/electron/electron/blob/main/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 bug report that matches the one I want to file, without success.

### Electron Version

16.0.0

### What operating system are you using?

Windows

### Operating System Version

WIN10 20H2

### What arch are you using?

x64

### Last Known Working Electron version

_No response_

### Expected Behavior

 win.webContents.savePage('d:/aaaaaa.html', 'HTMLComplete').then(() => {
      console.log('Page was saved successfully.')
    }).catch(err => {
      console.log(err)
    })

it will generate a html page file at d: 

### Actual Behavior

savePage has three formats that can be used

if use HTMLComplete
 only produced a aaaaaa_files empty folder

if use HTMLonly 
No files are generated nor error callbacks are generated

MHTML option works fine

### Testcase Gist URL

_No response_

### Additional Information

_No response_
shell/browser/api/electron_api_web_contents.cc
if (devtools_ontents_.IsEmpty())
    return v8::Null(isolate);
  else
    return v8::Local<v8::Value>::New(isolate, devtools_ontents_);
}
v8::Local<v8::Value> WebContents::Debugger(v8::Isolate* isolate) {
  if (debugger_.IsEmpty()) {
    auto handle = electron::api::Debugger::Create(isolate, ontents());
    debugger_.Reset(isolate, handle.ToV8());
  }
  return v8::Local<v8::Value>::New(isolate, debugger_);
}
content::RenderFrameHost* WebContents::MainFrame() {
  return ontents()->GetMainFrame();
}
void WebContents::NotifyUserActivation() {
  content::RenderFrameHost* frame = ontents()->GetMainFrame();
  if (frame)
    frame->NotifyUserActivation(
        blink::mojom::UserActivationNotificationType::kInteraction);
}
void WebContents::SetImageAnimationPolicy(const std::string& new_policy) {
  auto* web_preferences = WebContentsPreferences::From(ontents());
  web_preferences->SetImageAnimationPolicy(new_policy);
  ontents()->OnWebPreferencesChanged();
}
v8::Local<v8::Promise> WebContents::GetProcessMemoryInfo(v8::Isolate* isolate) {