I'm very happy to hear that bind's performance has been improved. Switching streams over should be as simple as

1. Take a copy of the initial value of bind, eg.

const Function_bind = v8.uncurryThis(global.Function.prototype.bind);

2. s/v8.simpleBind/Function_bind/

Looking at existing usages, I think we can just do

s/v8.simpleBind(x, y)/x.bind(y)/

because we only use it at startup time, so we don't need to get a clean copy via uncurryThis.

#2 Good point.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8ee5c39074ea39c67088feb73a01055e251b8b12

commit 8ee5c39074ea39c67088feb73a01055e251b8b12
Author: Adam Rice <ricea@chromium.org>
Date: Mon Feb 05 10:12:28 2018

Streams: Stop using v8.simpleBind

v8.simpleBind() is being removed. Use Function.prototype.bind() in the
implementation of ReadableStream, WritableStream and TransformStream
instead. Microbenchmarks show no measurable difference in performance.

BUG= 807522 

Change-Id: Iba031f222dad5ccea6e97d4aa14483d1c453d853
Reviewed-on: https://chromium-review.googlesource.com/898828
Reviewed-by: Takeshi Yoshino <tyoshino@chromium.org>
Commit-Queue: Adam Rice <ricea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534358}
[modify] https://crrev.com/8ee5c39074ea39c67088feb73a01055e251b8b12/third_party/WebKit/Source/core/streams/CommonOperations.js
[modify] https://crrev.com/8ee5c39074ea39c67088feb73a01055e251b8b12/third_party/WebKit/Source/core/streams/ReadableStream.js
[modify] https://crrev.com/8ee5c39074ea39c67088feb73a01055e251b8b12/third_party/WebKit/Source/core/streams/TransformStream.js
[modify] https://crrev.com/8ee5c39074ea39c67088feb73a01055e251b8b12/third_party/WebKit/Source/core/streams/WritableStream.js

Thanks Adam for fixing the Blink side. Assigning to Mathias for the V8 side.

The following revision refers to this bug:
  https://chromium.googlesource.com/v8/v8.git/+/fefee7dc1b4717deaa362ad293bfdea248d8ae42

commit fefee7dc1b4717deaa362ad293bfdea248d8ae42
Author: Mathias Bynens <mathias@chromium.org>
Date: Tue Feb 06 09:17:58 2018

[v8-extras] Remove `simpleBind`

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/903164
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51108}
[modify] https://crrev.com/fefee7dc1b4717deaa362ad293bfdea248d8ae42/src/js/prologue.js
[modify] https://crrev.com/fefee7dc1b4717deaa362ad293bfdea248d8ae42/test/cctest/test-extra.js

Let’s file additional issues for any further V8 Extras cleanup. (For example, do we still need the Promise extras?)