Able to reproduce the issue on Mac 10.11.6 using 54.0.2826.0.

Unable to do tool bisect as issue is seen only after signing into chrome which can't be done in chromium builds.

Manual Bisect info:
Good build:54.0.2824.0 Dev
Bad build:54.0.2825.0 Dev

CHANGE-LOG:
https://chromium.googlesource.com/chromium/src/+log/54.0.2824.0..54.0.2825.0?pretty=fuller&n=10000

Suspecting https://codereview.chromium.org/2229443003 from change-log.

@dpapad: Please help in re-assigning if it is not related to your change.

Adding Stable blocker label as it is recent regression.

After my change at https://codereview.chromium.org/2229443003, the dom-if <template name="sync"> node is inside another dom-if template. When visiting the URL directly, the following happens,
 - Line at [1] executes first, returning early.
 - Line at [2] executes after, returns true, but it is too late at this point, no-one is stamping the inner template.

[1] https://cs.chromium.org/chromium/src/chrome/browser/resources/settings/settings_page/settings_animated_pages.js?l=142
[2] https://cs.chromium.org/chromium/src/chrome/browser/resources/settings/people_page/people_page.js?q=people_page.js&l=299

I have an alternative fix which seems to satisfy both searching and direct navigation to the advanced sync settings page at https://codereview.chromium.org/2235323002.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a629fcba45a437827cfc2ac36fba9ad97b6bb3f1

commit a629fcba45a437827cfc2ac36fba9ad97b6bb3f1
Author: dpapad <dpapad@chromium.org>
Date: Fri Aug 12 00:01:07 2016

MD Settings: Fix advanced sync page reload.

A blank page was shown on direct navigation after
https://codereview.chromium.org/2229443003. It turns out that wrapping a
settings-subpage's dom-if within another dom-if is problematic, because the
settings-animated-pages ensureSubpageInstance_() executes before the outer
dom-if has been evaluated to true, leaving the page blank.

Fixed by removing the nested dom-if and using the no-search attribute instead,
to instruct the searching algorithm when to ignore the "advanced sync settings"
page.

BUG= 636816 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2235323002
Cr-Commit-Position: refs/heads/master@{#411459}

[modify] https://crrev.com/a629fcba45a437827cfc2ac36fba9ad97b6bb3f1/chrome/browser/resources/settings/people_page/people_page.html

Tested the issue on Windows 7, Mac 10.11.6, Ubuntu 14.04 using 54.0.2830.0.Sync setup page is not blank after CTRL+R or F5.
Please find attached screencast.

Marking it as TE-Verified.

Deleted: 636816.mp4 499 KB

	636816.mp4 499 KB View Download