Fix reload of a tab that crashed in background.

Fix reload of a tab that crashed in background.

This patch fixes a trivial mistake that made the fix in
https://codereview.chromium.org/459613007 a noop, and adds a regression
unit-test.

BUG=401859
Committed: https://crrev.com/7017a81991de983e12ab50dfc071c70e06979531
Cr-Commit-Position: refs/heads/master@{#291765}

[ppi, 2014-08-25 15:26:32]

Hi Alex, ptal. Sigh.

[aelias_OOO_until_Jul13, 2014-08-25 18:40:30]

lgtm

[ppi, 2014-08-25 20:09:08]

The CQ bit was checked by ppi@chromium.org

[commit-bot: I haz the power, 2014-08-25 20:09:45]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/ppi@chromium.org/498293002/1

[commit-bot: I haz the power, 2014-08-25 21:09:04]

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

[commit-bot: I haz the power, 2014-08-25 21:56:29]

Committed patchset #1 (1) as 897a10a3efc940ef39f2bb7e0f78a2d905b83571

[commit-bot: I haz the power, 2014-09-10 02:37:43]

Patchset 1 (id:??) landed as
https://crrev.com/7017a81991de983e12ab50dfc071c70e06979531
Cr-Commit-Position: refs/heads/master@{#291765}