Remove Oilpan-specific clearing of DOMWindow during document detach.

Remove Oilpan-specific clearing of DOMWindow during document detach.

Keep the observable lifetime of this object equal to what it is non-Oilpan.

R=haraken
BUG=420515
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=189240

[sof, 2015-01-29 22:53:56]

sigbjornf@opera.com changed reviewers:
+ oilpan-reviews@chromium.org

[sof, 2015-01-29 22:53:57]

Please take a look/consider.

The clearing of the DOMWindow on document detach is an Oilpan change made some
time ago without a particularly strong motivation; it makes some sense to let go
of the DOMWindow at that point, but not much more (afaicr.)

The fairly hairy test fast/dom/defaultView-on-detached-document.html fails w/
Oilpan because of it however, as it manages to peek at a Document's DOMWindow
when detached.

So, in the interest of not having Oilpan-specific&observable behavior here, I
suggest we consider reverting the DOMWindow  clearing.

[haraken, 2015-01-30 09:46:18]

LGTM. I think this change is safe.

[sof, 2015-01-30 10:08:50]

The CQ bit was checked by sigbjornf@opera.com

[commit-bot: I haz the power, 2015-01-30 10:09:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/883393002/1

[commit-bot: I haz the power, 2015-01-30 10:12:12]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=189240