[Win] Fix crash if the profile dir cannot be created

[Win] Fix crash if the profile dir cannot be created

If the profile is NULL, the code will hit the CHECK on line 389 anyway.

BUG=414332
Committed: https://crrev.com/82e87d588df3a7334cf542ce68c9614869745f70
Cr-Commit-Position: refs/heads/master@{#313709}

[noms (inactive), 2015-01-29 03:09:15]

noms@chromium.org changed reviewers:
+ sky@chromium.org

[noms (inactive), 2015-01-29 03:09:16]

If the profile cannot be initialized, then Chrome crashes when the profile tries
to be used. This crash only happens in dev and canary, where the NewProfileMgmt
flag is set. Adding this check would make sure Chrome behaves in the same way 
with-and-without the experiment (i.e. CHECKs a couple of lines below). Please
take a look. Thanks!

[sky, 2015-01-29 14:26:10]

LGTM

[noms (inactive), 2015-01-29 14:38:37]

The CQ bit was checked by noms@chromium.org

[commit-bot: I haz the power, 2015-01-29 14:39:33]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/878143003/1

[commit-bot: I haz the power, 2015-01-29 15:28:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-29 15:29:10]

Patchset 1 (id:??) landed as
https://crrev.com/82e87d588df3a7334cf542ce68c9614869745f70
Cr-Commit-Position: refs/heads/master@{#313709}