Using the per-revision bisect providing the bisect results, (*correction in Good & bad builds) 
Good Build: 58.0.3001.0 (Revision: 447896)
Bad Build: 58.0.3002.0 (Revision: 448123)

You are probably looking for a change made after 447904 (known good), but no later than 447905 (first known bad).CHANGELOG URL:
The script might not always return single CL as suspectas some perf builds might get missing due to failure.
  https://chromium.googlesource.com/chromium/src/+log/1b48ba269c836ccff3c6f9cc76210f04d791e824..b69c81cc077bc63f12c61a46528dff5ce22e9985

dpapad@ could you please check the issue and update.

Site settings are behind a flag and will not be included in 1st launch. Lowering the priority.

Strangely enough, I can still navigate to chrome://md-settings/content/all even with the flag disabled. Can we remove that page altogether?

Currently we use the loadTimeData 'enableSiteSettings' boolean to prevent the user from navigating via clicks to the "all sites" page, see [1]. But we don't prevent the user from navigating by URL. See [2] where the URL is still registered in the Router, and [3] where the HTML code is not guarded by any special condition.

[1] https://cs.chromium.org/chromium/src/chrome/browser/resources/settings/site_settings/site_list.js?l=408
[2] 
[3] https://cs.chromium.org/chromium/src/chrome/browser/resources/settings/privacy_page/privacy_page.html?l=207

I have a potential fix at https://codereview.chromium.org/2741343010.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/480869caaa149d728cbc2381476dbb5a153dc652

commit 480869caaa149d728cbc2381476dbb5a153dc652
Author: dpapad <dpapad@chromium.org>
Date: Thu Mar 16 01:39:32 2017

MD Settings: Prevent direct navigation to disabled Site Settings UI.

BUG=699421
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2741343010
Cr-Commit-Position: refs/heads/master@{#457303}

[modify] https://crrev.com/480869caaa149d728cbc2381476dbb5a153dc652/chrome/browser/resources/settings/compiled_resources2.gyp
[modify] https://crrev.com/480869caaa149d728cbc2381476dbb5a153dc652/chrome/browser/resources/settings/route.html
[modify] https://crrev.com/480869caaa149d728cbc2381476dbb5a153dc652/chrome/browser/resources/settings/route.js
[modify] https://crrev.com/480869caaa149d728cbc2381476dbb5a153dc652/chrome/test/data/webui/settings/cr_settings_browsertest.js
[modify] https://crrev.com/480869caaa149d728cbc2381476dbb5a153dc652/chrome/test/data/webui/settings/site_list_tests.js

crrev.com/457303 fixed the case where the disabled UI was showing up when it should not. The problems within the "all sites" view are separate, and since this view is not part of the initial MD Settings launch, this is a lower priority.

For the record, there is an exception thrown in the console that might be related (see attachment where the C++ call to getSiteDetails fails).

Deleted: console_error.png 187 KB

	console_error.png 187 KB View Download

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

Sorry for the inconvenience if the bug really should have been left as Available.

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