The `simpleBind` function exposed by V8 Extras was initially added to
work around the terrible performance of `Function.prototype.bind` at
the time. Nowadays `Function.prototype.bind` is significantly faster
and fully optimized by TurboFan, however, so there’s no need for the
`simpleBind` helper anymore.

Bug: chromium:807522
Change-Id: I1a0456e2aa34f92a3c9a0234a812b660f969d016
Reviewed-on: https://chromium-review.googlesource.com/903164Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51108}