Revert of Skip nullptr after copyToVector() from HeapHashSet<WeakMember>

Revert of Skip nullptr after copyToVector() from HeapHashSet<WeakMember> (patchset #2 id:20001 of https://codereview.chromium.org/2723033002/ )

Reason for revert:
Reverting because we have other fixes for the cause we suspected. See http://crbug.com/696231 for more details.

Original issue's description:
> Skip nullptr after copyToVector() from HeapHashSet<WeakMember>
> 
> This patch checks and skips nullptr after copyToVector() from
> HeapHashSet<WeakMember>.
> 
> This is a speculative fix.
> 
> BUG=581698, 689949, 696231
> 
> Review-Url: https://codereview.chromium.org/2723033002
> Cr-Commit-Position: refs/heads/master@{#453890}
> Committed: https://chromium.googlesource.com/chromium/src/+/9dc4f6ff6d59eb2c27e3723a61e53f1430a9c192

TBR=haraken@chromium.org,sigbjornf@opera.com
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=581698, 689949, 696231
Review-Url: https://codereview.chromium.org/2783483003
Cr-Commit-Position: refs/heads/master@{#460142}
Committed: https://chromium.googlesource.com/chromium/src/+/64bb332d22780352a0d2dbbd802d158aa9664af0

[kojii, 2017-03-28 14:31:26]

The CQ bit was checked by kojii@chromium.org

[kojii, 2017-03-28 14:31:27]

Created Revert of Skip nullptr after copyToVector() from HeapHashSet<WeakMember>

[commit-bot: I haz the power, 2017-03-28 14:31:52]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[sof, 2017-03-28 14:47:54]

lgtm

[haraken, 2017-03-28 15:51:36]

LGTM

[commit-bot: I haz the power, 2017-03-28 17:07:50]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1490711486896740, "parent_rev":
"bb7522e6433d4aa05dd81026c42559f9ca2011e6", "commit_rev":
"64bb332d22780352a0d2dbbd802d158aa9664af0"}

[commit-bot: I haz the power, 2017-03-28 17:08:38]

Description was changed from

==========
Revert of Skip nullptr after copyToVector() from HeapHashSet<WeakMember>
(patchset #2 id:20001 of https://codereview.chromium.org/2723033002/ )

Reason for revert:
Reverting because we have other fixes for the cause we suspected. See
http://crbug.com/696231 for more details.

Original issue's description:
> Skip nullptr after copyToVector() from HeapHashSet<WeakMember>
> 
> This patch checks and skips nullptr after copyToVector() from
> HeapHashSet<WeakMember>.
> 
> This is a speculative fix.
> 
> BUG=581698, 689949, 696231
> 
> Review-Url: https://codereview.chromium.org/2723033002
> Cr-Commit-Position: refs/heads/master@{#453890}
> Committed:
https://chromium.googlesource.com/chromium/src/+/9dc4f6ff6d59eb2c27e3723a61e5...

TBR=haraken@chromium.org,sigbjornf@opera.com
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=581698, 689949, 696231
==========

to

==========
Revert of Skip nullptr after copyToVector() from HeapHashSet<WeakMember>
(patchset #2 id:20001 of https://codereview.chromium.org/2723033002/ )

Reason for revert:
Reverting because we have other fixes for the cause we suspected. See
http://crbug.com/696231 for more details.

Original issue's description:
> Skip nullptr after copyToVector() from HeapHashSet<WeakMember>
> 
> This patch checks and skips nullptr after copyToVector() from
> HeapHashSet<WeakMember>.
> 
> This is a speculative fix.
> 
> BUG=581698, 689949, 696231
> 
> Review-Url: https://codereview.chromium.org/2723033002
> Cr-Commit-Position: refs/heads/master@{#453890}
> Committed:
https://chromium.googlesource.com/chromium/src/+/9dc4f6ff6d59eb2c27e3723a61e5...

TBR=haraken@chromium.org,sigbjornf@opera.com
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=581698, 689949, 696231

Review-Url: https://codereview.chromium.org/2783483003
Cr-Commit-Position: refs/heads/master@{#460142}
Committed:
https://chromium.googlesource.com/chromium/src/+/64bb332d22780352a0d2dbbd802d...
==========

[commit-bot: I haz the power, 2017-03-28 17:08:39]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/64bb332d22780352a0d2dbbd802d...