You are probably looking for a change made after 442777 (known good), but no later than 442788 (first known bad).
CHANGELOG URL:
  https://chromium.googlesource.com/chromium/src/+log/e45198cfa72d361281a496ea16e794fe4aac64c7..04a7d729155baecab68fde4bedac49d5a1d1e9aa


Likely regressor:
https://chromium.googlesource.com/chromium/src/+/37240b4fdef1ec7017f59d4cb7ced8c655e5c595

gah - yeah I'll need to update the constants in website_settings_popup_view.cc so that it works with/without --secondary-ui-md

So actually I think this is a regression from two CLs that landed really close together.

r442683 (kylixrd) landed while r442779 (tapted) was in flight and changed some of the assumptions.

There's a change on r442683 that doesn't look right: https://codereview.chromium.org/2571613002/diff/160001/ui/views/bubble/bubble_dialog_delegate.cc#newcode109 changes the title margins for non-material from

gfx::Insets(kPanelVertMargin, kPanelHorizMargin, 0, kPanelHorizMargin)

(== 13/13/0/13)

to

views_delegate->GetDialogFrameViewInsets()

which (on non-harmony) is

gfx::Insets ViewsDelegate::GetDialogFrameViewInsets() {
  return gfx::Insets(kPanelVertMargin, kButtonHEdgeMarginNew, 0,
                     kButtonHEdgeMarginNew);
}

(== 13/20/0/20).


In any case, it looks like, since r442683, website_settings_popup_view now needs to deal with dynamic title margins. I think the neat way to do that is by exposing a title_margins_ member on BubbleDialogDelegate (which we tried not to do in https://codereview.chromium.org/2581493002, but things are different now :).

possible CL to fix: https://codereview.chromium.org/2640593002

How the dialog looks with/without --secondary-ui-md after the CL in https://codereview.chromium.org/2640593002

Deleted: oib_views.png 180 KB

	oib_views.png 180 KB View Download

Deleted: oib_harmony.png 164 KB

	oib_harmony.png 164 KB View Download

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/57b697aa2605b6bbcb97352a32ccdb28204739e9

commit 57b697aa2605b6bbcb97352a32ccdb28204739e9
Author: tapted <tapted@chromium.org>
Date: Wed Jan 18 20:50:56 2017

Fix alignment of title/content on the OIB / Site Settings bubble.

r442683 adopted a dynamic inset for the title in bubble dialogs in order
to align with the content under Harmony. Shortly after, r442779 landed
and adopted the default bubble title view for the site settings bubble,
rather than providing a custom one. Title and content should always be
aligned on the site settings bubble (regardless of Harmony), so it now
needs to be aware of whether the title in the dialog is inset or not.

Harmony will align title and content by default. Otherwise, to fix
alignment for the site settings bubble, explicitly set the title margins
to match the content margins.

BUG= 681081 

Review-Url: https://codereview.chromium.org/2640593002
Cr-Commit-Position: refs/heads/master@{#444474}

[modify] https://crrev.com/57b697aa2605b6bbcb97352a32ccdb28204739e9/chrome/browser/ui/views/website_settings/website_settings_popup_view.cc
[modify] https://crrev.com/57b697aa2605b6bbcb97352a32ccdb28204739e9/ui/views/bubble/bubble_dialog_delegate.cc
[modify] https://crrev.com/57b697aa2605b6bbcb97352a32ccdb28204739e9/ui/views/bubble/bubble_dialog_delegate.h