The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7

commit d79887d431cc6fb7e494f92ac763c2b50d7fb0e7
Author: calamity <calamity@chromium.org>
Date: Fri Jul 14 04:43:56 2017

[MD Bookmarks] Refactor focus ring hiding.

This CL refactors how mouse focus hides the focus ring by moving the
listener into the app and using keyboard events to restore the focus ring
instead of blur event. This reduces the number of event listeners and deals
well with window focus/blur.

BUG= 740834 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2981503002
Cr-Commit-Position: refs/heads/master@{#486675}

[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/app.html
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/app.js
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/compiled_resources2.gyp
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/dialog_focus_manager.html
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/dialog_focus_manager.js
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/folder_node.html
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/folder_node.js
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/item.html
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/item.js
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/mouse_focus_behavior.js
[modify] https://crrev.com/d79887d431cc6fb7e494f92ac763c2b50d7fb0e7/chrome/browser/resources/md_bookmarks/shared_style.html

Tested on Mac OS 10.12.5 using Chrome Dev version M61 - 61.0.3159.5 as per the issue mentioned in the original comment. Please refer the screencast attached.

Steps followed:
1. Added few bookmarks.
2. Navigated to Chrome://bookmarks.
3. Click on Menu button of any bookmark. A menu is displayed.
4. Add a new tab and navigate back to Bookmarks tab.
5. Dismiss the Menu.

Observations: Selection of Bookmark and round focus on the Bookmark menu are seen.

@calamity -- Could you please confirm whether the focus displayed is as expected or not, so that it would help us in triaging the issue further by adding TE-Verified labels.

Thank you!

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/715b2a4381954f5b310b6abc49bb9fb734ba01f6

commit 715b2a4381954f5b310b6abc49bb9fb734ba01f6
Author: Christopher Lam <calamity@chromium.org>
Date: Tue Jul 25 03:09:57 2017

[MD Bookmarks] Fix some focus ring bugs.

This CL fixes an issue with the focus ring appearing on modifier key
presses and makes the focus ring appear on up and down arrow on the
list which was broken due to event retargeting shenanigans.

Bug:  740834 
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Id75c17596fccfd066cc97bae3a73150146d4ba26
Reviewed-on: https://chromium-review.googlesource.com/580172
Reviewed-by: Tim Sergeant <tsergeant@chromium.org>
Commit-Queue: calamity <calamity@chromium.org>
Cr-Commit-Position: refs/heads/master@{#489204}
[modify] https://crrev.com/715b2a4381954f5b310b6abc49bb9fb734ba01f6/chrome/browser/resources/md_bookmarks/mouse_focus_behavior.js
[modify] https://crrev.com/715b2a4381954f5b310b6abc49bb9fb734ba01f6/chrome/test/data/webui/md_bookmarks/app_test.js