Revert of Introduce cross_site_iframe_factory.html, and use it in a test

Revert of Introduce cross_site_iframe_factory.html, and use it in a test (patchset #9 id:150001 of https://codereview.chromium.org/1264923002/ )

Reason for revert:
Fails on Windows Vista and Mac 10.6

http://build.chromium.org/p/chromium.win/builders/Vista%20Tests%20(1)/builds/58432
http://build.chromium.org/p/chromium.mac/builders/Mac10.6%20Tests/builds/5408

../../chrome/browser/site_details_browsertest.cc:121: Failure
Value of: details->uma()->GetAllSamples( "SiteIsolation.IsolateAllSitesTotalProcessCountEstimate")
Expected: has 1 element that is equal to Bucket 11: 1
  Actual: { Bucket 10: 1 }, whose element #0 doesn't match

Original issue's description:
> Introduce cross_site_iframe_factory.html, and use it to test
> the site isolation code in MemoryMetricsDetails under chrome/.
>
> [ See crbug.com/515672 for a screenshot ]
>
> /cross_site_iframe_factory.html?a(b(c, d)) gives you a simple three-level,
> four-site iframe test. The trick it uses, is that the query parameter
> is parsed and passed recursively to children, so the first level is:
>
>     <iframe src="b.com:1234/cross_site_iframe_factory.html?b(c(),d())">
>
> Which then contains the two leaf iframes:
>
>     <iframe src="c.com:1234/cross_site_iframe_factory.html?c()">
>     <iframe src="d.com:1234/cross_site_iframe_factory.html?d()">
>
> To to cut down on noise. ".com" is automatically affixed to the hostname
> if a TLD isn't present.
>
> As a convenience, the page supports local preview if loaded via file:// URI.
> file:// URIs are technically cross-origin, although --site-per-process doesn't
> isolate them today.
>
> Each site has a random (but consistent) background color as a visual aid.
> The page contains some crude layout logic to make sure the outer levels
> are big enough to fit the inner levels.
>
> The parsing logic is in tree_parser_util.js, which has unittests.
>
> MetricsMemoryDetailsBrowserTest.TestSiteIsolation is a new test
> that uses the above facility to creates a bunch of complex iframe
> cases, and tests that our process-counting UMA stats are as expected.
>
> BUG=515672
>
> Committed: https://crrev.com/02292e994c9ec62deecec3bec2132500ca68a5de
> Cr-Commit-Position: refs/heads/master@{#342447}

TBR=dcheng@chromium.org,asvitkine@chromium.org,jam@chromium.org,nick@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=515672
Committed: https://crrev.com/324d28e8e26f11bc88a96181eb029658dbe441c6
Cr-Commit-Position: refs/heads/master@{#342473}

[nasko, 2015-08-07 23:15:54]

Created Revert of Introduce cross_site_iframe_factory.html, and use it in a test

[commit-bot: I haz the power, 2015-08-07 23:17:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1282623002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1282623002/1

[commit-bot: I haz the power, 2015-08-07 23:19:57]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-08-07 23:20:34]

Patchset 1 (id:??) landed as
https://crrev.com/324d28e8e26f11bc88a96181eb029658dbe441c6
Cr-Commit-Position: refs/heads/master@{#342473}