Remove Weak{Map,Set}.prototype.clear.

Remove Weak{Map,Set}.prototype.clear.

Per Nov 2014 TC39 decision.

R=adamk@chromium.org
LOG=Y

Committed: https://chromium.googlesource.com/v8/v8/+/49ab2312e23e275393bc735694680400909d9e0e

[Dmitry Lomov (no reviews), 2014-11-19 20:27:18]

PTAL

[adamk, 2014-11-19 20:35:03]

I'm very surprised to hear that this is being changed so late in the game.
According to:

http://kangax.github.io/compat-table/es6/#WeakMap

WeakMap.prototype.clear is present in the latest versions of IE, Firefox,
Safari, Opera, and Chrome. For Chrome, it's been exposed for around six months.

If we're going to remove this, I think it'd ideally be done with a flag so we
can easily reverse course if it turns out this breaks content we care about.

[Dmitry Lomov (no reviews), 2014-11-19 21:16:47]

On 2014/11/19 20:35:03, adamk wrote:
> I'm very surprised to hear that this is being changed so late in the game.
> According to:
> 
> http://kangax.github.io/compat-table/es6/#WeakMap
> 
> WeakMap.prototype.clear is present in the latest versions of IE, Firefox,
> Safari, Opera, and Chrome. For Chrome, it's been exposed for around six
months.
> 
> If we're going to remove this, I think it'd ideally be done with a flag so we
> can easily reverse course if it turns out this breaks content we care about.

I am not sure what the flag will solve here - we can revert the CL if worse
comes to worse.

[arv (Not doing code reviews), 2014-11-19 21:16:54]

arv@chromium.org changed reviewers:
+ arv@chromium.org

[arv (Not doing code reviews), 2014-11-19 21:16:54]

LGTM

This was never approved for ES6. It was a "bug" in the spec.

[adamk, 2014-11-19 21:23:32]

On 2014/11/19 21:16:47, Dmitry Lomov (chromium) wrote:
> On 2014/11/19 20:35:03, adamk wrote:
> > I'm very surprised to hear that this is being changed so late in the game.
> > According to:
> > 
> > http://kangax.github.io/compat-table/es6/#WeakMap
> > 
> > WeakMap.prototype.clear is present in the latest versions of IE, Firefox,
> > Safari, Opera, and Chrome. For Chrome, it's been exposed for around six
> months.
> > 
> > If we're going to remove this, I think it'd ideally be done with a flag so
we
> > can easily reverse course if it turns out this breaks content we care about.
> 
> I am not sure what the flag will solve here - we can revert the CL if worse
> comes to worse.

OK, lgtm if you're fine with that. I was under the impression that we were
trying to get away from having to make code changes when we broke stuff on a
release branch, but I'll admit that this'll be a pretty straightforward revert
if it comes to that.

[Dmitry Lomov (no reviews), 2014-11-19 21:26:11]

The CQ bit was checked by dslomov@chromium.org

[commit-bot: I haz the power, 2014-11-19 21:26:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/739303002/1

[commit-bot: I haz the power, 2014-11-19 21:52:56]

Committed patchset #1 (id:1)