Revert of [heap] Cleanup mark bit usage.

Revert of [heap] Cleanup mark bit usage. (patchset #1 id:1 of https://codereview.chromium.org/1474203003/ )

Reason for revert:
Still investigating bad canary.

Original issue's description:
> [heap] Cleanup mark bit usage.
>
> BUG=
>
> Committed: https://crrev.com/5874ac783ff9bc4bb4b2fda81f5077f06619f96c
> Cr-Commit-Position: refs/heads/master@{#32362}

TBR=mlippautz@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Committed: https://crrev.com/d3faef8658598e68331208b5a1846ac1c250cb49
Cr-Commit-Position: refs/heads/master@{#32461}

[Hannes Payer (out of office), 2015-12-01 13:28:31]

Created Revert of [heap] Cleanup mark bit usage.

[commit-bot: I haz the power, 2015-12-01 13:28:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1490753003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1490753003/1

[commit-bot: I haz the power, 2015-12-01 13:29:34]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-12-01 13:29:53]

Description was changed from

==========
Revert of [heap] Cleanup mark bit usage. (patchset #1 id:1 of
https://codereview.chromium.org/1474203003/ )

Reason for revert:
Still investigating bad canary.

Original issue's description:
> [heap] Cleanup mark bit usage.
> 
> BUG=
> 
> Committed: https://crrev.com/5874ac783ff9bc4bb4b2fda81f5077f06619f96c
> Cr-Commit-Position: refs/heads/master@{#32362}

TBR=mlippautz@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=
==========

to

==========
Revert of [heap] Cleanup mark bit usage. (patchset #1 id:1 of
https://codereview.chromium.org/1474203003/ )

Reason for revert:
Still investigating bad canary.

Original issue's description:
> [heap] Cleanup mark bit usage.
>
> BUG=
>
> Committed: https://crrev.com/5874ac783ff9bc4bb4b2fda81f5077f06619f96c
> Cr-Commit-Position: refs/heads/master@{#32362}

TBR=mlippautz@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Committed: https://crrev.com/d3faef8658598e68331208b5a1846ac1c250cb49
Cr-Commit-Position: refs/heads/master@{#32461}
==========

[commit-bot: I haz the power, 2015-12-01 13:29:53]

Patchset 1 (id:??) landed as
https://crrev.com/d3faef8658598e68331208b5a1846ac1c250cb49
Cr-Commit-Position: refs/heads/master@{#32461}

[Hannes Payer (out of office), 2015-12-02 11:03:22]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1488393003/ by hpayer@chromium.org.

The reason for reverting is: Reland after fixing the potential root cause of the
canary crasher..