### 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
gin_helper::Arguments* args) {
  ui::ScopedClipboardWriter writer(GetClipboardBuffer(args));
  base::string16 text, html, bookmark;
  gfx::Image image;
  if (data.Get("text", &text)) {
    writer.WriteText(text);
    if (data.Get("bookmark", &bookmark))
      writer.WriteBookmark(bookmark, base::UTF16ToUTF8(text));
  }
  if (data.Get("rtf", &text)) {
    std::string rtf = base::UTF16ToUTF8(text);
    writer.WriteRTF(rtf);
  }
  if (data.Get("html", &html))
    writer.WriteHTML(html, std::string());
  if (data.Get("image", &image))
    writer.WriteImage(image.AsBitmap());
}
base::string16 Clipboard::ReadText(gin_helper::Arguments* args) {