Revert of Various ASan exemptions to allow Oilpan pre-sweep poisoning of unmarkeds.

Revert of Various ASan exemptions to allow Oilpan pre-sweep poisoning of unmarkeds. (patchset #6 id:100001 of https://codereview.chromium.org/1120943002/)

Reason for revert:
Broke non-Oilpan ASAN compilation,

 http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20ASAN/builds/18615

Original issue's description:
> Various ASan exemptions to allow Oilpan pre-sweep poisoning of unmarkeds.
> 
> Heap objects must not access other dead objects while finalizing.
> To help catch out those that do, the Oilpan GC can now poison 
> unmarked, to-be-swept objects. To be able to make use of that
> with ASan enabled, a couple of benign accesses that run afoul
> of that strict check are still needed & must be allowed to
> make this feasible.
> 
> Here provided together -- the ones related to Timer stopping &
> removal from the timer heap aren't something we'd typically want
> to impose one the Blink codebase in general, but beside the
> goal of better ASan coverage, the timer heap will soon be removed
> and the need for these should fall away.
> 
> R=haraken,tkent,yutak
> BUG=420515
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=195609

TBR=haraken@chromium.org,yutak@chromium.org,tkent@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=420515
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=195611

[sof, 2015-05-20 11:05:42]

Created Revert of Various ASan exemptions to allow Oilpan pre-sweep poisoning of
unmarkeds.

[commit-bot: I haz the power, 2015-05-20 11:05:50]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1144933004/1

[commit-bot: I haz the power, 2015-05-20 11:06:22]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=195611

[tkent, 2015-05-20 23:30:38]

lgtm