### Issue Details

* **Electron Version:**
  * `8.3.3`
* **Operating System:**
  * Windows 10 2004
* **Last Known Working Electron version:**
  * `7.x`

### Expected Behavior
You can write and read from clipboard via `Buffer`.

### Actual Behavior
You can write but not read.

### To Reproduce

```js
setTimeout(() => {
  clipboard.writeBuffer('code/file-list', Buffer.from("Hello World"));
  console.log("did write")
}, 1000);

setTimeout(() => {
  const res = clipboard.readBuffer('code/file-list');
  console.log(res.toString());
}, 2000);
```

The output is empty with Electron 8 but filled with Electron 7.

//cc @deepak1556 
shell/common/api/electron_api_clipboard.cc
std::string type;
  if (args->GetNext(&type) && type == "selection")
    return ui::ClipboardBuffer::kSelection;
  else
    return ui::ClipboardBuffer::kCopyPaste;
}
std::vector<base::string16> Clipboard::AvailableFormats(
    gin_helper::Arguments* args) {
  std::vector<base::string16> format_types;
  ui::Clipboard* clipboard = ui::Clipboard::GetForCurrentThread();
  clipboard->ReadAvailableTypes(GetClipboardBuffer(args), &format_types);
  return format_types;
}
bool Clipboard::Has(const std::string& format_string,
                    gin_helper::Arguments* args) {
  ui::Clipboard* clipboard = ui::Clipboard::GetForCurrentThread();
  ui::ClipboardFormatType format(
      ui::ClipboardFormatType::GetType(format_string));
  return clipboard->IsFormatAvailable(format, GetClipboardBuffer(args));
}
std::string Clipboard::Read(const std::string& format_string) {