Implement ES6 Array.prototype.toString behind --harmony-tostring

ES6 Array.prototype.toString falls back on Object.prototype.toString if method "join" is not callable.

BUG=v8:3793
LOG=Y
R=dslomov@chromium.org, arv@chromium.org

Committed: https://crrev.com/12af28309a125acfe428e8cbbe2a1754d6b87f07
Cr-Commit-Position: refs/heads/master@{#26253}

[caitp (gmail), 2015-01-03 15:31:59]

The bug turned out to be invalid, but there's a little typo fixup, so I thought
I'd try to get that in. Should be trivial

[caitp (gmail), 2015-01-03 15:58:50]

On 2015/01/03 15:31:59, caitp wrote:
> The bug turned out to be invalid, but there's a little typo fixup, so I
thought
> I'd try to get that in. Should be trivial

I was wrong, there's something to this bug, so adding a bit more substance to
this CL

[arv (Not doing code reviews), 2015-01-12 15:46:39]

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

[arv (Not doing code reviews), 2015-01-12 15:46:40]

https://codereview.chromium.org/835753002/diff/20001/src/harmony-tostring.js
File src/harmony-tostring.js (right):

https://codereview.chromium.org/835753002/diff/20001/src/harmony-tostring.js#...
src/harmony-tostring.js:45: if (IS_ARRAY(this) && this.join === ArrayJoin) {
It looks like we are doing Get(object, 'join') twice?

https://codereview.chromium.org/835753002/diff/20001/src/harmony-tostring.js#...
src/harmony-tostring.js:52: return %_CallFunction(O, ObjectToStringHarmony);
Could we just change ArrayToString to use DefaultObjectToString instead of
duplicating ArrayToString?

https://codereview.chromium.org/835753002/diff/20001/src/harmony-tostring.js#...
src/harmony-tostring.js:99: DefineOwnProperty($Array.prototype, "toString",
desc, false);
DefineOwnProperty takes a descriptor... can we use a lower level API (above too)
that does not require that temporary descriptor object?

[caitp (gmail), 2015-01-12 15:53:16]

https://codereview.chromium.org/835753002/diff/20001/src/harmony-tostring.js
File src/harmony-tostring.js (right):

https://codereview.chromium.org/835753002/diff/20001/src/harmony-tostring.js#...
src/harmony-tostring.js:52: return %_CallFunction(O, ObjectToStringHarmony);
On 2015/01/12 15:46:40, arv wrote:
> Could we just change ArrayToString to use DefaultObjectToString instead of
> duplicating ArrayToString?

hmm, that's a good point

https://codereview.chromium.org/835753002/diff/20001/src/harmony-tostring.js#...
src/harmony-tostring.js:99: DefineOwnProperty($Array.prototype, "toString",
desc, false);
On 2015/01/12 15:46:40, arv wrote:
> DefineOwnProperty takes a descriptor... can we use a lower level API (above
too)
> that does not require that temporary descriptor object?

Sort of --- Runtime_AddOwnProperty (used by InstallFunctions) will throw if the
property already exists (in debug mode only).

There's a `RUNTIME_ASSERT(!it.IsFound());` in there which causes that, I'm not
sure if it's a good idea to remove it

[caitp (gmail), 2015-01-12 16:43:03]

Patchset #4 (id:60001) has been deleted

[Dmitry Lomov (no reviews), 2015-01-23 13:20:44]

lgtm

[arv (Not doing code reviews), 2015-01-23 14:50:16]

LGTM

[caitp (gmail), 2015-01-23 14:58:01]

The CQ bit was checked by caitpotter88@gmail.com

[commit-bot: I haz the power, 2015-01-23 14:58:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/835753002/40001

[commit-bot: I haz the power, 2015-01-23 15:21:35]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-01-23 15:21:54]

Patchset 3 (id:??) landed as
https://crrev.com/12af28309a125acfe428e8cbbe2a1754d6b87f07
Cr-Commit-Position: refs/heads/master@{#26253}