Track empty username and password in PasswordStore.

Track empty username and password in PasswordStore.

Having both username and password empty is incorrect. We should find out where they come from.

BUG=404012
Committed: https://crrev.com/0ae57a5355e1c95ca53861b06a330d690b94fd11
Cr-Commit-Position: refs/heads/master@{#292135}

[vasilii, 2014-08-27 10:48:16]

vasilii@chromium.org changed reviewers:
+ vabr@chromium.org

[vasilii, 2014-08-27 10:48:16]

please check that one too as a follow-up.

[vabr (Chromium), 2014-08-27 10:57:40]

LGTM.
Also, thanks for explaining. Just for the record if anybody else wonders why
landing this CL right after https://codereview.chromium.org/512673002/: I
understand now that putting the guard in the password store (as opposed to login
database as in https://codereview.chromium.org/493123002), which is outside of
the path used by sync, will show the cause of introducing the invalid forms (as
opposed to reporting on every occasion sync moves the introduced form around).

Cheers,
Vaclav

[vasilii, 2014-08-27 11:08:39]

The CQ bit was checked by vasilii@chromium.org

[commit-bot: I haz the power, 2014-08-27 11:09:11]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/vasilii@chromium.org/514573002/1

[commit-bot: I haz the power, 2014-08-27 11:56:58]

Committed patchset #1 (1) as fddf0096cf70c7bff00b460ed50dccdc0e2b5652

[commit-bot: I haz the power, 2014-09-10 02:51:07]

Patchset 1 (id:??) landed as
https://crrev.com/0ae57a5355e1c95ca53861b06a330d690b94fd11
Cr-Commit-Position: refs/heads/master@{#292135}