Implement all entry points in libGLES and have libEGL act as a shim. This allows libANGLE to only be included in libGLESv2 and moves all TLS data to libGLESv2.dll. BUG=angle:733 Change-Id: I34f0b47987a5efbe906c290d3ca656142e69ea9a Reviewed-on: https://chromium-review.googlesource.com/232962 Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>