Fix initialization of thread local storage in libGLESv2. When an app would load libGLESv2.dll via LoadModule, then would call methods on a thread that was already created, we could creash because of uninitialized thread local storage. BUG=angle:488 Change-Id: I9b05de462232a16d639c58ec07386b7c38a01793 Reviewed-on: https://chromium-review.googlesource.com/179132 Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Geoff Lang <geofflang@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>