Revert of Enable the bootstrap sandbox by default.

Revert of Enable the bootstrap sandbox by default. (patchset #3 id:40001 of https://codereview.chromium.org/1352623003/ )

Reason for revert:
Caused Mac 10.10 layout failures: http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Mac10.10/builds/4593

Original issue's description:
> Enable the bootstrap sandbox by default.
>
> This will place renderer processes under the bootstrap sandbox. This can be
> disabled with --disable-bootstrap-sandbox.
>
> BUG=367863
>
> Committed: https://crrev.com/2dded5291bc5e9427721e1a06c74f2a80a86e8fa
> Cr-Commit-Position: refs/heads/master@{#350006}

TBR=avi@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=367863
Committed: https://crrev.com/f1422520b42e8fa5b4ffe75359af96bac75d67b0
Cr-Commit-Position: refs/heads/master@{#350065}

[Robert Sesek, 2015-09-21 23:39:53]

Created Revert of Enable the bootstrap sandbox by default.

[commit-bot: I haz the power, 2015-09-21 23:40:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1355043004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1355043004/1

[commit-bot: I haz the power, 2015-09-21 23:41:48]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-21 23:42:41]

Patchset 1 (id:??) landed as
https://crrev.com/f1422520b42e8fa5b4ffe75359af96bac75d67b0
Cr-Commit-Position: refs/heads/master@{#350065}

[Robert Sesek, 2015-09-21 23:47:53]

On 2015/09/21 23:39:53, Robert Sesek wrote:
> Created Revert of Enable the bootstrap sandbox by default.

https://code.google.com/p/chromium/issues/detail?id=534650

[Robert Sesek, 2015-09-29 18:31:07]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1372343004/ by rsesek@chromium.org.

The reason for reverting is: Fixed issue that was the cause of the revert,
https://crbug.com/534650..