Android accessibility: automatically focus links

Android accessibility: automatically focus links

When setting accessibility focus to a node, auto-focus it if it's a link.
This is needed for some sites that have skip links that are only visible
when focused. It might be possible to auto-focus more than just links but
this seems the safest.

Fixing this exposed a race condition with our code to refocus the node with
accessibility focus if its location has changed - essentially when you
click on the skip link, the skip link was changing its location, causing us
to fire notifications on it because its location had changed - but that
was racing with the real change to accessibility focus from following the
skip link.

Fix this race condition by re-focusing the node with accessibility focus
after a short delay, and canceling the delayed task if accessibility
focus changes again.

Tested manually with two urls that exercise these code paths.

BUG=657157
TESTED=http://getbootstrap.com/ and http://jsfiddle.net/mev0c4dt/show/

Committed: https://crrev.com/fd9566093da77d9413ba61f8be1b6e03daaadf33
Cr-Commit-Position: refs/heads/master@{#430006}

[dmazzoni, 2016-11-02 18:25:36]

Description was changed from

==========
Android accessibility: automatically focus links

When setting accessibility focus to a node, auto-focus it if it's a link.
This is needed for some sites that have skip links that are only visible
when focused. It might be possible to auto-focus more than just links but
this seems the safest.

BUG=657157
==========

to

==========
Android accessibility: automatically focus links

When setting accessibility focus to a node, auto-focus it if it's a link.
This is needed for some sites that have skip links that are only visible
when focused. It might be possible to auto-focus more than just links but
this seems the safest.

Fixing this exposed a race condition with our code to refocus the node with
accessibility focus if its location has changed - essentially when you
click on the skip link, the skip link was changing its location, causing us
to fire notifications on it because its location had changed - but that
was racing with the real change to accessibility focus from following the
skip link.

Fix this race condition by re-focusing the node with accessibility focus
after a short delay, and canceling the delayed task if accessibility
focus changes again.

Tested manually with two urls that exercise these code paths.

BUG=657157
TESTED=http://getbootstrap.com/ and http://jsfiddle.net/mev0c4dt/show/
==========

[dmazzoni, 2016-11-02 18:25:36]

dmazzoni@chromium.org changed reviewers:
+ dtseng@chromium.org, sgurun@chromium.org

[sgurun-gerrit only, 2016-11-04 01:44:21]

On 2016/11/02 18:25:43, dmazzoni wrote:

lgtm

[dmazzoni, 2016-11-04 16:50:28]

The CQ bit was checked by dmazzoni@chromium.org

[commit-bot: I haz the power, 2016-11-04 16:51:00]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-04 16:54:42]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-04 16:54:43]

Try jobs failed on following builders:
  ios-device on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device/builds...)

[dmazzoni, 2016-11-04 19:59:03]

The CQ bit was checked by dmazzoni@chromium.org

[dmazzoni, 2016-11-04 19:59:03]

The patchset sent to the CQ was uploaded after l-g-t-m from sgurun@chromium.org
Link to the patchset: https://codereview.chromium.org/2465403003/#ps40001
(title: "Rebase")

[commit-bot: I haz the power, 2016-11-04 19:59:38]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-04 20:40:36]

Description was changed from

==========
Android accessibility: automatically focus links

When setting accessibility focus to a node, auto-focus it if it's a link.
This is needed for some sites that have skip links that are only visible
when focused. It might be possible to auto-focus more than just links but
this seems the safest.

Fixing this exposed a race condition with our code to refocus the node with
accessibility focus if its location has changed - essentially when you
click on the skip link, the skip link was changing its location, causing us
to fire notifications on it because its location had changed - but that
was racing with the real change to accessibility focus from following the
skip link.

Fix this race condition by re-focusing the node with accessibility focus
after a short delay, and canceling the delayed task if accessibility
focus changes again.

Tested manually with two urls that exercise these code paths.

BUG=657157
TESTED=http://getbootstrap.com/ and http://jsfiddle.net/mev0c4dt/show/
==========

to

==========
Android accessibility: automatically focus links

When setting accessibility focus to a node, auto-focus it if it's a link.
This is needed for some sites that have skip links that are only visible
when focused. It might be possible to auto-focus more than just links but
this seems the safest.

Fixing this exposed a race condition with our code to refocus the node with
accessibility focus if its location has changed - essentially when you
click on the skip link, the skip link was changing its location, causing us
to fire notifications on it because its location had changed - but that
was racing with the real change to accessibility focus from following the
skip link.

Fix this race condition by re-focusing the node with accessibility focus
after a short delay, and canceling the delayed task if accessibility
focus changes again.

Tested manually with two urls that exercise these code paths.

BUG=657157
TESTED=http://getbootstrap.com/ and http://jsfiddle.net/mev0c4dt/show/
==========

[commit-bot: I haz the power, 2016-11-04 20:40:39]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-11-04 20:42:36]

Description was changed from

==========
Android accessibility: automatically focus links

When setting accessibility focus to a node, auto-focus it if it's a link.
This is needed for some sites that have skip links that are only visible
when focused. It might be possible to auto-focus more than just links but
this seems the safest.

Fixing this exposed a race condition with our code to refocus the node with
accessibility focus if its location has changed - essentially when you
click on the skip link, the skip link was changing its location, causing us
to fire notifications on it because its location had changed - but that
was racing with the real change to accessibility focus from following the
skip link.

Fix this race condition by re-focusing the node with accessibility focus
after a short delay, and canceling the delayed task if accessibility
focus changes again.

Tested manually with two urls that exercise these code paths.

BUG=657157
TESTED=http://getbootstrap.com/ and http://jsfiddle.net/mev0c4dt/show/
==========

to

==========
Android accessibility: automatically focus links

When setting accessibility focus to a node, auto-focus it if it's a link.
This is needed for some sites that have skip links that are only visible
when focused. It might be possible to auto-focus more than just links but
this seems the safest.

Fixing this exposed a race condition with our code to refocus the node with
accessibility focus if its location has changed - essentially when you
click on the skip link, the skip link was changing its location, causing us
to fire notifications on it because its location had changed - but that
was racing with the real change to accessibility focus from following the
skip link.

Fix this race condition by re-focusing the node with accessibility focus
after a short delay, and canceling the delayed task if accessibility
focus changes again.

Tested manually with two urls that exercise these code paths.

BUG=657157
TESTED=http://getbootstrap.com/ and http://jsfiddle.net/mev0c4dt/show/

Committed: https://crrev.com/fd9566093da77d9413ba61f8be1b6e03daaadf33
Cr-Commit-Position: refs/heads/master@{#430006}
==========

[commit-bot: I haz the power, 2016-11-04 20:42:37]

Patchset 3 (id:??) landed as
https://crrev.com/fd9566093da77d9413ba61f8be1b6e03daaadf33
Cr-Commit-Position: refs/heads/master@{#430006}

[aelias_OOO_until_Jul13, 2017-01-03 22:43:20]

A revert of this CL (patchset #3 id:40001) has been created in
https://codereview.chromium.org/2609313002/ by aelias@chromium.org.

The reason for reverting is: Caused scrolling bug http://crbug.com/675567

BUG=657157,675567.