Using the per-revision bisect providing the bisect results,
Good build: 55.0.2845.0 (Revision: 415522).
Bad build: 55.0.2846.0 (Revision: 415833).

You are probably looking for a change made after 415655 (known good), but no later than 415656 (first known bad).
CHANGELOG URL:
  https://chromium.googlesource.com/chromium/src/+log/d57cd741ffc0f5e9328222c0f73d3519b4aae9fb..93cfbbd07e3ee8d9465147a1be2601a0cb74632e

@krb -- Could you please look into the issue, pardon me if it has nothing to do with your changes and if possible please assign it to concern owner

Hi msr,

This should have been fixed at 417932.

Issue looks to be related to incorrect positioning of USB permission bubble as per this report and attached screenshot in C#0 is still seen on the latest canary(55.0.2875.0).

krb@: Could you please confirm if the present position of bubble is WAI or not?

Removing the blocker label as the issue repros only behind the flag. Add it back if someone feels otherwise.

Thank you!

Hi ajha,

I can't get the USB or Bluetooth notifications to pop-up, I assume due to a hardware issue, but all the other notifications "point" to the "Expected" place per the PNG in the problem description. Do the other notifications e.g. Notifications work for you?

Please Enable 'Experimental Web Platform features' flag under chrome://flags to check the pop up.

It still doesn't show with http. Hope that's WAI. But it does with https, and it's showing the same problem as the earlier bubbles. I'll take a look.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b34fa9422ed84323d7d20ebc9eb69bb946207e87

commit b34fa9422ed84323d7d20ebc9eb69bb946207e87
Author: krb <krb@chromium.org>
Date: Fri Sep 30 13:14:28 2016

[omnibox] Return reference to ImageView instead of LocationIconView (2)

Found another place where we need to return a reference to the
ImageView, not the LocationIconView.

From the previous CL:

The latter is quite wide when we fill in the label half of it, which we
now do with site security level in some cases.  The bubble (in the bug
that is in the wrong place) anchors to the middle of whatever View you
return to it, so we really want to give it the padlock here.

BUG= 650140 

Review-Url: https://codereview.chromium.org/2379783003
Cr-Commit-Position: refs/heads/master@{#422094}

[modify] https://crrev.com/b34fa9422ed84323d7d20ebc9eb69bb946207e87/chrome/browser/ui/views/website_settings/chooser_bubble_ui_view.cc

Please let me know if this does or doesn't address your case.

Tested the issue on Windows -- Chrome Dev# 55.0.2880.0 and on Linux -- Chrome Dev# 55.0.2879.0 and is no more reproducible.
Hence adding TE-Verified-Labels.
Attached a screen shot for reference.
Thank You.

Deleted: 650140.png 154 KB

	650140.png 154 KB View Download