Revert "Remove early bail-out in VisitWeakList to investigate chrasher."

Revert "Remove early bail-out in VisitWeakList to investigate chrasher."

>  BUG=468601
>  LOG=n
>
>  Review URL: https://codereview.chromium.org/1016353002
>
>  Cr-Commit-Position: refs/heads/master@{#27317}

R=hpayer@chromium.org
BUG=v8:3996, chromium:468601
LOG=n

Committed: https://crrev.com/835eeafe32f442d7b43fe175237de2c70ed7ceef
Cr-Commit-Position: refs/heads/master@{#27814}

[Hannes Payer (out of office), 2015-04-14 10:37:38]

lgtm

[jochen (gone - plz use gerrit), 2015-04-14 10:53:57]

The CQ bit was checked by jochen@chromium.org

[commit-bot: I haz the power, 2015-04-14 10:54:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1080303002/1

[commit-bot: I haz the power, 2015-04-14 10:55:30]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-14 10:55:39]

Patchset 1 (id:??) landed as
https://crrev.com/835eeafe32f442d7b43fe175237de2c70ed7ceef
Cr-Commit-Position: refs/heads/master@{#27814}

[jochen (gone - plz use gerrit), 2015-04-16 20:59:44]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1092783002/ by jochen@chromium.org.

The reason for reverting is: Still doesn't work.