Reland "[heap] Don't unmap new space pages while sweeping is active"

[heap] Don't unmap new space pages while sweeping is active

- Avoid unmapping of new space pages while sweeping using a delayed list that
  gets emptied upon the next call to the unmapper.

BUG=chromium:628984
R=hpayer@chromium.org

This reverts commit 4a1f2807d6da046367afd243159e40275ad9f8c6.

Committed: https://crrev.com/ece2f1084b97d4b5bffa6a3b3004a45a9366ff94
Cr-Commit-Position: refs/heads/master@{#38715}

[Michael Lippautz, 2016-08-18 11:34:22]

Patchset #2 (id:20001) has been deleted

[Michael Lippautz, 2016-08-18 11:35:17]

Description was changed from

==========
Reland "[heap] Don't unmap new space pages while sweeping is active"

This reverts commit 4a1f2807d6da046367afd243159e40275ad9f8c6.

BUG=
==========

to

==========
[heap] Don't unmap new space pages while sweeping is active

- Avoid unmapping of new space pages while sweeping using a delayed list that
  gets emptied upon the next call to the unmapper.

BUG=chromium:628984
R=hpayer@chromium.org

This reverts commit 4a1f2807d6da046367afd243159e40275ad9f8c6.
==========

[Michael Lippautz, 2016-08-18 11:35:17]

mlippautz@chromium.org changed reviewers:
+ hpayer@chromium.org

[Michael Lippautz, 2016-08-18 11:35:52]

we need the new space barrier as this ensure us that all pages in new space are
iterable and don't contain pointers to dead objects

[Hannes Payer (out of office), 2016-08-18 11:36:22]

lgtm

[Michael Lippautz, 2016-08-18 11:39:27]

The CQ bit was checked by mlippautz@chromium.org

[commit-bot: I haz the power, 2016-08-18 11:39:34]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-18 12:16:39]

Description was changed from

==========
[heap] Don't unmap new space pages while sweeping is active

- Avoid unmapping of new space pages while sweeping using a delayed list that
  gets emptied upon the next call to the unmapper.

BUG=chromium:628984
R=hpayer@chromium.org

This reverts commit 4a1f2807d6da046367afd243159e40275ad9f8c6.
==========

to

==========
[heap] Don't unmap new space pages while sweeping is active

- Avoid unmapping of new space pages while sweeping using a delayed list that
  gets emptied upon the next call to the unmapper.

BUG=chromium:628984
R=hpayer@chromium.org

This reverts commit 4a1f2807d6da046367afd243159e40275ad9f8c6.
==========

[commit-bot: I haz the power, 2016-08-18 12:16:40]

Committed patchset #2 (id:40001)

[commit-bot: I haz the power, 2016-08-18 12:17:05]

Description was changed from

==========
[heap] Don't unmap new space pages while sweeping is active

- Avoid unmapping of new space pages while sweeping using a delayed list that
  gets emptied upon the next call to the unmapper.

BUG=chromium:628984
R=hpayer@chromium.org

This reverts commit 4a1f2807d6da046367afd243159e40275ad9f8c6.
==========

to

==========
[heap] Don't unmap new space pages while sweeping is active

- Avoid unmapping of new space pages while sweeping using a delayed list that
  gets emptied upon the next call to the unmapper.

BUG=chromium:628984
R=hpayer@chromium.org

This reverts commit 4a1f2807d6da046367afd243159e40275ad9f8c6.

Committed: https://crrev.com/ece2f1084b97d4b5bffa6a3b3004a45a9366ff94
Cr-Commit-Position: refs/heads/master@{#38715}
==========

[commit-bot: I haz the power, 2016-08-18 12:17:06]

Patchset 2 (id:??) landed as
https://crrev.com/ece2f1084b97d4b5bffa6a3b3004a45a9366ff94
Cr-Commit-Position: refs/heads/master@{#38715}