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### Issue Details
app.clearRecentDocuments does not work on Windows.


* **Electron Version:**
  * 5.0.8
* **Operating System:**
  * Windows 10 pro; build 1903
* **Last Known Working Electron version:**
  * <!-- (if applicable) e.g. 3.1.0 -->

### Expected Behavior
List of recent documents should be cleared

### Actual Behavior
List of recent documents continues to accumulate

### To Reproduce
Try `app.clearRecentDocuments();` on Windows

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### Screenshots
![image](https://user-images.githubusercontent.com/670682/62343120-307b8f00-b4f2-11e9-853e-a8aac23b8ecd.png)
![image](https://user-images.githubusercontent.com/670682/62343111-20fc4600-b4f2-11e9-8277-189fe6f0a69b.png)

### Additional Information
<!-- Add any other context about the problem here. -->

shell/browser/browser_win.cc
if (!GetProtocolLaunchPath(args, &exe))
    return false;
  if (keyVal == exe) {
    
    if (FAILED(classesKey.DeleteKey(shellPath.c_str())))
      return false;
    
    base::win::RegKey protocolKey;
    base::string16 protocolPath = keyPath + wprotocol;
    if (SUCCEEDED(
            protocolKey.Open(root, protocolPath.c_str(), KEY_ALL_ACCESS))) {
      protocolKey.DeleteValue(L"URL Protocol");
      
      protocolKey.WriteValue(L"", L"");
      protocolKey.DeleteValue(L"");
    }
    
    classesKey.DeleteEmptyKey(wprotocol.c_str());
    return true;
  } else {
    return true;
  }
}
bool Browser::SetAsDefaultProtocolClient(const std::string& protocol,
                                         mate::Arguments* args) {