ES6 computed property names

ES6 computed property names

This adds support for computed property names, under the flag
--harmony-computed-property-names, for both object literals and
classes.

This is a revert of the revert, a76419f0f497db156eb1010e9b4be398951280cb.

This changes to do an early bailout in
HOptimizedGraphBuilder::VisitObjectLiteral instead of doing that in the later
loop.

BUG=v8:3754
LOG=Y
TBR=dslomov@chromium.org

Committed: https://crrev.com/cc568d1b7ae7ff9f870f21aaad6698e2cd6cd9d2
Cr-Commit-Position: refs/heads/master@{#25868}

[arv (Not doing code reviews), 2014-12-17 18:07:26]

The only difference from last time is in hydrogen.cc

[Dmitry Lomov (no reviews), 2014-12-17 18:10:10]

lgtm

[arv (Not doing code reviews), 2014-12-17 18:10:46]

The CQ bit was checked by arv@chromium.org

[commit-bot: I haz the power, 2014-12-17 18:11:28]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/792233008/1

[commit-bot: I haz the power, 2014-12-17 18:38:47]

Committed patchset #1 (id:1)

[Michael Achenbach, 2014-12-17 19:46:34]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/811593004/ by machenbach@chromium.org.

The reason for reverting is: [sheriff] Still crashes on win32 (XP):
http://build.chromium.org/p/client.v8/builders/V8%20Win32%20-%201/builds/1380.

[Jakob Kummerow, 2014-12-17 20:03:33]

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

[Jakob Kummerow, 2014-12-17 20:03:33]

DBC:

(1) When relanding, recommended practice is to upload the original patch as a
first patch set, then any modifications as subsequent patch sets. That way,
reviewers can easily tell what's changed.

(2) IIRC, the plan was to implement all ES6 features such that a simple flag
flip is enough to turn them off if the need arises. It would appear that
following this principle would also avoid the churn of repeatedly
landing/reverting 1000+ line patches, and at the same time test that the
emergency off switch works ;-)

[arv (Not doing code reviews), 2014-12-17 20:16:29]

On 2014/12/17 20:03:33, Jakob wrote:
> DBC:
> 
> (1) When relanding, recommended practice is to upload the original patch as a
> first patch set, then any modifications as subsequent patch sets. That way,
> reviewers can easily tell what's changed.

That's a good idea. I'll do that next time.

> (2) IIRC, the plan was to implement all ES6 features such that a simple flag
> flip is enough to turn them off if the need arises. It would appear that
> following this principle would also avoid the churn of repeatedly
> landing/reverting 1000+ line patches, and at the same time test that the
> emergency off switch works ;-)

This is under a flag that is off by default. The crash is in a test that tests
the new feature. We could keep the code and just disable the test but then we
would have a large chunk of code that is not being tested which is also bad.

[commit-bot: I haz the power, 2014-12-18 18:05:05]

Patchset 1 (id:??) landed as
https://crrev.com/cc568d1b7ae7ff9f870f21aaad6698e2cd6cd9d2
Cr-Commit-Position: refs/heads/master@{#25868}