Shifted code for CheckInternetZoneIdentifier into its own test so its flakiness

Shifted code for CheckInternetZoneIdentifier into its own test so its flakiness
doesn't poison rest of the browser tests.

BUG=20809
TEST=All DownloadTest.* browser tests pass except for 20809 specific one (windows)

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=72537

[Randy Smith (Not in Mondays), 2011-01-23 17:48:46]

Andy, Pawel: Could you take a quick look at this for me?  I don't think we need
to bother Brett with this change, but feel free to pull him in if you disagree.

Once this change goes in, I'll commit a change enabling all the download browser
tests and hopefully watch the tree *not* get all flaky over the next couple of
days :-}.

[ahendrickson, 2011-01-23 20:52:31]

LGTM.

On 2011/01/23 17:48:46, rdsmith wrote:
> Andy, Pawel: Could you take a quick look at this for me?  I don't think we
need
> to bother Brett with this change, but feel free to pull him in if you
disagree.
> 
> Once this change goes in, I'll commit a change enabling all the download
browser
> tests and hopefully watch the tree *not* get all flaky over the next couple of
> days :-}.

[Paweł Hajdan Jr., 2011-01-24 08:55:40]

LGTM, thanks!