Password bubble: Deal correctly with blacklist state changes.

Password bubble: Deal correctly with blacklist state changes.

If a user blacklists or unblacklists a site in a separate tab, we need
to correctly update every other tab's state (consider the unlikely case
of logging into the same site 8 times at the same time in separate tabs,
or the slightly less unlikely case of changing status in
chrome://settings/passwords while a login page is visible). This CL updates
the observer logic to account for blacklist entries being added and removed
from the PasswordStore, and updates the UI accordingly.

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This is a reland of r269244, which was reverted due to LSAN breakage.
Original review at https://codereview.chromium.org/276683003/
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BUG=261628
TBR=vabr@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=269583

[Mike West, 2014-05-09 14:25:32]

The CQ bit was checked by mkwst@chromium.org

[Mike West, 2014-05-09 14:26:01]

TBRing you, Vaclav; this CL implements the ScopedVector change that we
discussed.

-mike

[commit-bot: I haz the power, 2014-05-09 14:27:15]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/mkwst@chromium.org/276583003/1

[Mike West, 2014-05-09 14:27:21]

The CQ bit was checked by mkwst@chromium.org

[commit-bot: I haz the power, 2014-05-09 14:34:10]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/mkwst@chromium.org/276583003/20001

[vabr (Chromium), 2014-05-09 14:45:05]

LGTM, thanks!

[commit-bot: I haz the power, 2014-05-09 16:21:42]

FYI, CQ is re-trying this CL (attempt #1).
Please consider checking whether the failures are real,
and report flakes to chrome-troopers@google.com.
The failing builders are:
  android_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/android_dbg/builds/18...)

[commit-bot: I haz the power, 2014-05-10 18:04:11]

Change committed as 269583