Shorten mangled names of types This will reduce binary size by a few kilobytes once we store mangled names of functions as constexpr strings. This still keeps mangled names human readable. BUG=angleproject:2267 TEST=angle_unittests Change-Id: Ia63980bd511c701a93e2c5e247d24578c7d7f332 Reviewed-on: https://chromium-review.googlesource.com/943101 Commit-Queue: Olli Etuaho <oetuaho@nvidia.com> Reviewed-by: Jamie Madill <jmadill@chromium.org>