MSOpenTech/thread — pull request #1 by mauve (2014-06-01 19:01:30+00:00)
Title: Use __declspec(thread) instead of Tls/Fls functions in WinRT and WinPRT

The Fls* family of functions is supported in Windows Store apps but not
in Windows Phone apps, however __declspec(thread) works in both so let's
use that instead.