Oilpan: fix WebSocket unit tests memory leaks.

Oilpan: fix WebSocket unit tests memory leaks.

Remove unnecessary Persistent reference (to an object contained within
another Persistent) + arrange for manual GCing of resources to avoid
test objects being reported as not destructed and leaking with
Oilpan enabled.

R=
BUG=

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=175233

[sof, 2014-06-01 21:28:52]

Please take a look.

Addresses the webkit_unit_tests seen with Oilpan enabled (cf.
https://codereview.chromium.org/298893008/ )

Note: ToT is suffering from another Oilpan webkit_unit_tests breakage (
http://build.chromium.org/p/tryserver.blink/builders/mac_blink_oilpan_dbg/bui...
) in IDTransactionTest::EnsureLifetime. It does not reproduce with a local build
based on r175151, so it appears rather recent. It's not related to this CL.

[sof, 2014-06-01 21:34:10]

Just in case this isn't known.. one added reason for caring about
webkit_unit_tests failures is that the Oilpan trybots will not run webkit_tests
if the webkit_unit_tests step fails, for some reason. This blocks other CLs from
being able to do much testing wrt ToT.

[tkent, 2014-06-01 23:03:04]

lgtm

[commit-bot: I haz the power, 2014-06-01 23:03:12]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sigbjornf@opera.com/306273002/1

[haraken, 2014-06-01 23:16:50]

LGTM, thanks!

[commit-bot: I haz the power, 2014-06-01 23:48:21]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  mac_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/mac_blink_rel/builds/9762)

[commit-bot: I haz the power, 2014-06-02 00:22:54]

Change committed as 175233

[tyoshino (SeeGerritForStatus), 2014-06-02 03:59:25]

lgtm

[yhirano, 2014-06-02 04:38:33]

lgtm, thanks for doing this!

[sof, 2014-06-02 05:01:51]

On 2014/06/02 04:38:33, yhirano wrote:
> lgtm, thanks for doing this!

Excellent, thanks for the quick reviews and handing it over to CQ right away.