+yury any ideas?

I think re-skin causes this, will take a look.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e94e3762c55e8098cb403b776b9818f4f4188985

commit e94e3762c55e8098cb403b776b9818f4f4188985
Author: khmel <khmel@google.com>
Date: Fri Aug 25 00:37:57 2017

arc: Fix ToS layout animation.

Webview has badly looking animation for initial layout. This easy
catches eyes. Based on previous ARC OptIn UI implementation, reliable
workaround is to provide fixed Webview width. The same trick applies to
OOBE ARC Optin which is also affected by this problem.

Bug:  758132 
Test: Manually.
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I981e89c731375eed111439bc22b08a61cecbefe1
Reviewed-on: https://chromium-review.googlesource.com/633873
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Yury Khmel <khmel@google.com>
Cr-Commit-Position: refs/heads/master@{#497269}
[modify] https://crrev.com/e94e3762c55e8098cb403b776b9818f4f4188985/chrome/browser/resources/chromeos/arc_support/main.css
[modify] https://crrev.com/e94e3762c55e8098cb403b776b9818f4f4188985/chrome/browser/resources/chromeos/arc_support/main.html
[modify] https://crrev.com/e94e3762c55e8098cb403b776b9818f4f4188985/chrome/browser/resources/chromeos/login/arc_terms_of_service.css

I nominate this as Release  blocker M61. Besides the problem described in header, we found and fixed one more visual regression, please see attached pic.

Deleted: one_more_problem.png 99 KB

	one_more_problem.png 99 KB View Download

Changed milestone as in prev comment. Please revert to M62 or approve merge. Thanks!

This bug requires manual review: We are only 10 days from stable.
Please contact the milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), ketakid@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Approving merge to M61 Chrome OS.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/67a2aa762bceb49c88ddf8170f024542206277a4

commit 67a2aa762bceb49c88ddf8170f024542206277a4
Author: khmel <khmel@google.com>
Date: Fri Aug 25 15:28:08 2017

[Merge M61] arc: Fix ToS layout animation.

Webview has badly looking animation for initial layout. This easy
catches eyes. Based on previous ARC OptIn UI implementation, reliable
workaround is to provide fixed Webview width. The same trick applies to
OOBE ARC Optin which is also affected by this problem.

Bug:  758132 
Test: Manually.
TBR=khmel@google.com, xiyuan@chromium.org

(cherry picked from commit e94e3762c55e8098cb403b776b9818f4f4188985)

Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I981e89c731375eed111439bc22b08a61cecbefe1
Reviewed-on: https://chromium-review.googlesource.com/633873
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Yury Khmel <khmel@google.com>
Cr-Original-Commit-Position: refs/heads/master@{#497269}
Reviewed-on: https://chromium-review.googlesource.com/635907
Reviewed-by: Yury Khmel <khmel@chromium.org>
Cr-Commit-Position: refs/branch-heads/3163@{#888}
Cr-Branched-From: ff259bab28b35d242e10186cd63af7ed404fae0d-refs/heads/master@{#488528}
[modify] https://crrev.com/67a2aa762bceb49c88ddf8170f024542206277a4/chrome/browser/resources/chromeos/arc_support/main.css
[modify] https://crrev.com/67a2aa762bceb49c88ddf8170f024542206277a4/chrome/browser/resources/chromeos/arc_support/main.html
[modify] https://crrev.com/67a2aa762bceb49c88ddf8170f024542206277a4/chrome/browser/resources/chromeos/login/arc_terms_of_service.css

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/234a4ebfea60319672f94f2fea0e1a92f8e4ae3c

commit 234a4ebfea60319672f94f2fea0e1a92f8e4ae3c
Author: lgcheng <lgcheng@google.com>
Date: Fri Aug 25 19:38:41 2017

Arc optin.

Add correct margin after removing mis-typed dot.

Bug:  758132 
Test: Manually.
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I4389b49bc64464fd81ff105dda16d31cfccd56df
Reviewed-on: https://chromium-review.googlesource.com/636283
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Long Cheng <lgcheng@google.com>
Cr-Commit-Position: refs/heads/master@{#497496}
[modify] https://crrev.com/234a4ebfea60319672f94f2fea0e1a92f8e4ae3c/chrome/browser/resources/chromeos/arc_support/main.css

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/554bcf5e17ecab8ec2b87002d3cd80cd9a2b47ef

commit 554bcf5e17ecab8ec2b87002d3cd80cd9a2b47ef
Author: lgcheng <lgcheng@google.com>
Date: Fri Aug 25 19:44:53 2017

[Merge M61]Arc optin.

Add correct margin after removing mis-typed dot.

TBR=xiyuan@chromium.org

Bug:  758132 
Test: Manually.
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I4389b49bc64464fd81ff105dda16d31cfccd56df
Reviewed-on: https://chromium-review.googlesource.com/636283
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Long Cheng <lgcheng@google.com>
Cr-Original-Commit-Position: refs/heads/master@{#497496}(cherry picked from commit 234a4ebfea60319672f94f2fea0e1a92f8e4ae3c)
Reviewed-on: https://chromium-review.googlesource.com/636226
Reviewed-by: Long Cheng <lgcheng@google.com>
Cr-Commit-Position: refs/branch-heads/3163@{#897}
Cr-Branched-From: ff259bab28b35d242e10186cd63af7ed404fae0d-refs/heads/master@{#488528}
[modify] https://crrev.com/554bcf5e17ecab8ec2b87002d3cd80cd9a2b47ef/chrome/browser/resources/chromeos/arc_support/main.css