Fixed SEGV that could happen if an exception is thrown during bootstrapping.

Fixed SEGV that could happen if an exception is thrown during bootstrapping.

BUG=chromium:487974
LOG=N

Committed: https://crrev.com/5bd4f9dd5a7f27042acbf845b3f84a32bc6c179e
Cr-Commit-Position: refs/heads/master@{#28453}

[Igor Sheludko, 2015-05-18 14:40:48]

ishell@chromium.org changed reviewers:
+ mstarzinger@chromium.org

[Igor Sheludko, 2015-05-18 14:40:49]

PTAL

[Michael Starzinger, 2015-05-18 14:46:32]

LGTM.

[Igor Sheludko, 2015-05-18 14:47:03]

The CQ bit was checked by ishell@chromium.org

[commit-bot: I haz the power, 2015-05-18 14:47:23]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1145703002/1

[commit-bot: I haz the power, 2015-05-18 14:48:59]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-05-18 14:49:00]

Try jobs failed on following builders:
  v8_linux64_avx2_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux64_avx2_rel/builds/447)

[Igor Sheludko, 2015-05-18 15:01:17]

The CQ bit was checked by ishell@chromium.org

[Igor Sheludko, 2015-05-18 15:01:17]

The patchset sent to the CQ was uploaded after l-g-t-m from
mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/1145703002/#ps40001
(title: "Rebasing #@$!")

[commit-bot: I haz the power, 2015-05-18 15:01:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1145703002/40001

[commit-bot: I haz the power, 2015-05-18 15:50:43]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-05-18 15:51:01]

Patchset 3 (id:??) landed as
https://crrev.com/5bd4f9dd5a7f27042acbf845b3f84a32bc6c179e
Cr-Commit-Position: refs/heads/master@{#28453}