[heap] Do not use page markbits in UnreachableObjectsFilter.

[heap] Do not use page markbits in UnreachableObjectsFilter.

Currently the UnreachableObjectsFilter does not work if incremental
marking is in progress since they both use the same markbits.

This patch changes the UnreachableObjectsFilter to use local markbits.

BUG=

Review-Url: https://codereview.chromium.org/2901553002
Cr-Commit-Position: refs/heads/master@{#45467}
Committed: https://chromium.googlesource.com/v8/v8/+/9b1d22fc2cf4fb95383937a8bca2f825ec942e46

[ulan, 2017-05-22 15:40:38]

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

[ulan, 2017-05-22 15:40:38]

ptal

[Hannes Payer (out of office), 2017-05-22 15:57:06]

lgtm

[ulan, 2017-05-22 15:57:41]

The CQ bit was checked by ulan@chromium.org

[commit-bot: I haz the power, 2017-05-22 15:57:45]

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, 2017-05-22 16:30:42]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1495468661102370,
"parent_rev": "b9df000343f2b6cdc366eab1fc54f858bf09d572", "commit_rev":
"9b1d22fc2cf4fb95383937a8bca2f825ec942e46"}

[commit-bot: I haz the power, 2017-05-22 16:30:49]

Description was changed from

==========
[heap] Do not use page markbits in UnreachableObjectsFilter.

Currently the UnreachableObjectsFilter does not work if incremental
marking is in progress since they both use the same markbits.

This patch changes the UnreachableObjectsFilter to use local markbits.

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

to

==========
[heap] Do not use page markbits in UnreachableObjectsFilter.

Currently the UnreachableObjectsFilter does not work if incremental
marking is in progress since they both use the same markbits.

This patch changes the UnreachableObjectsFilter to use local markbits.

BUG=

Review-Url: https://codereview.chromium.org/2901553002
Cr-Commit-Position: refs/heads/master@{#45467}
Committed:
https://chromium.googlesource.com/v8/v8/+/9b1d22fc2cf4fb95383937a8bca2f825ec9...
==========

[commit-bot: I haz the power, 2017-05-22 16:30:50]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/v8/v8/+/9b1d22fc2cf4fb95383937a8bca2f825ec9...