Allocate XMLHttpRequest on the eagerly finalized heap.

Allocate XMLHttpRequest on the eagerly finalized heap.

With XMLHttpRequest now being on the heap with !ENABLE(OILPAN), we need
to arrange for this ActiveDOMObject to be allocated as an eagerly
finalized object.

R=haraken
BUG=509841
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198853

[sof, 2015-07-14 09:00:33]

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

[sof, 2015-07-14 09:00:33]

please take a look.

Affects trunk builds (and M45..)

[haraken, 2015-07-14 09:05:47]

LGTM

[haraken, 2015-07-14 09:06:04]

haraken@chromium.org changed reviewers:
+ haraken@chromium.org

[haraken, 2015-07-14 09:06:05]

How did you notice this error?

[sof, 2015-07-14 09:08:48]

On 2015/07/14 09:06:05, haraken wrote:
> How did you notice this error?

By looking at the stack trace on the associated bug & seeing the regression
interval.

I've failed to come up with a reliable repro (i.e., trigger a GC that eagerly
finalizes the throttle object but not the XHR object.)

[sof, 2015-07-14 09:12:17]

On 2015/07/14 09:00:33, sof wrote:
> please take a look.
> 
> Affects trunk builds (and M45..)

This last bit is worth keeping in mind.. lazy sweeping & idle GCs (and
heap-allocated XHRs) are now enabled on M45. So, should there be trouble we will
need to handle backporting.

[sof, 2015-07-14 09:50:36]

The CQ bit was checked by sigbjornf@opera.com

[sof, 2015-07-14 09:50:37]

The patchset sent to the CQ was uploaded after l-g-t-m from haraken@chromium.org
Link to the patchset: https://codereview.chromium.org/1237063002/#ps40001
(title: "add macro for testing eager finalization")

[commit-bot: I haz the power, 2015-07-14 09:50:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1237063002/40001

[commit-bot: I haz the power, 2015-07-14 10:56:07]

Committed patchset #3 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=198853