uber: remove mouse focus outlines on nav tabs.

uber: remove mouse focus outlines on nav tabs.

They just go away as soon as the page (e.g. History) loads and it looks funky.

R=dmazzoni@chromium.org
BUG=457165
Committed: https://crrev.com/eb9e28a66036087fa627c7bd73dd7e3bfb524123
Cr-Commit-Position: refs/heads/master@{#316188}

[dmazzoni, 2015-02-12 16:48:19]

Sorry for the delay. Taking a closer look at how FocusOutlineManager is
implemented, I'm concerned about two things:

1. focusByKeyboard is only updated if the user presses *tab* - but a screen
reader user can move focus to an element using different keys - for example if
you use VO+left/right to move elements it will auto-focus the element you
navigate to. I think it should perhaps switch to keyboard mode on any key down,
not just "tab". (Even that isn't perfect, but it should be better.)

2. The event listeners are per-frame, so they aren't going to catch when the
user tabs into a control from another frame. For example: click on a link in the
uber frame - this sets focusByKeyboard to false. Now click in the frame for the
extensions/settings page. Now press Shift+Tab to move focus back into the
uberframe. Now you've focused one of those links via the keyboard, but
focusByKeyboard will be false because the key press originated in a different
frame.

[Dan Beam, 2015-02-13 05:57:24]

On 2015/02/12 16:48:19, dmazzoni wrote:
> Sorry for the delay. Taking a closer look at how FocusOutlineManager is
> implemented, I'm concerned about two things:
> 
> 1. focusByKeyboard is only updated if the user presses *tab* - but a screen
> reader user can move focus to an element using different keys - for example if
> you use VO+left/right to move elements it will auto-focus the element you
> navigate to. I think it should perhaps switch to keyboard mode on any key
down,
> not just "tab". (Even that isn't perfect, but it should be better.)

Done.

> 
> 2. The event listeners are per-frame, so they aren't going to catch when the
> user tabs into a control from another frame. For example: click on a link in
the
> uber frame - this sets focusByKeyboard to false. Now click in the frame for
the
> extensions/settings page. Now press Shift+Tab to move focus back into the
> uberframe. Now you've focused one of those links via the keyboard, but
> focusByKeyboard will be false because the key press originated in a different
> frame.

This particular example is fixed.  Please see updated code.

[dmazzoni, 2015-02-13 07:05:44]

The CQ bit was checked by dmazzoni@chromium.org

[dmazzoni, 2015-02-13 07:05:45]

lgtm

Thanks for taking care of those cases.

There may be more cases when it comes to iframes, we should be on the lookout.

[commit-bot: I haz the power, 2015-02-13 07:06:25]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/914033002/20001

[commit-bot: I haz the power, 2015-02-13 07:56:59]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-02-13 07:57:46]

Patchset 2 (id:??) landed as
https://crrev.com/eb9e28a66036087fa627c7bd73dd7e3bfb524123
Cr-Commit-Position: refs/heads/master@{#316188}