<filesystem>: Use of std::filesystem::path causes link error on UWP(already fixed)

[fsb4000]

Describe the bug
Use of std::filesystem::path causes link error on UWP

Command-line test case

1. Create default UWP C++ Project.
2. Add /std:c++17  flag
3. Add
#include <filesystem>
static auto myPath = std::filesystem::path("anyDir") / std::filesystem::path("anyFile.txt");

Expected behavior
Should work.
Actually it works.

The bug is already fixed: #322

STL version
Microsoft Visual Studio Community 2019
Version 16.6.4

Additional context
See more: VSO-718901 / AB#718901 | DevCom-369081

[StephanTLavavej]

Thanks for verifying that this was indeed fixed. (Apparently there was a second error that vanished, probably due to WinSDK updates; I've never known how to build UWP projects so I really appreciate your work here!) I've resolved the DevCom and VSO bugs accordingly.