Use dynamically sized containers for texture and sampler bindings. BUG=angle:685 Change-Id: I7af97a95deee69fbdebca2b57403244f45516e67 Reviewed-on: https://chromium-review.googlesource.com/216564 Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>