Fix initialization of thread local storage in libEGL. When an app would load libEGL.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: If3f73fb59dcc5f0713f5b6fb9ca9f8535ee23c73 Reviewed-on: https://chromium-review.googlesource.com/179131 Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Geoff Lang <geofflang@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>