Merge to M54: Don't post events on internal nodes in the accessibility tree on Android.

Merge to M54: Don't post events on internal nodes in the accessibility tree on Android.

Sometimes we get events on nodes in the internal accessibility tree that
are not exposed on that platform or under all circumstances. On Android
that led to an issue where after closing a SELECT pop-up, we got a focus
event on the OPTION and subsequent navigation was trapped inside that
control rather than outside it.

The fix is to map the focus event to the topmost leaf ancestor, which
in this case would be the SELECT element.

BUG=652805
Review-Url: https://codereview.chromium.org/2397503002
Cr-Commit-Position: refs/heads/master@{#422944}
(cherry picked from commit 7969d3a5bcf2af3fac57c3acef518298e8c48382)

Committed: https://chromium.googlesource.com/chromium/src/+/55a0dba38e5df7bea291c3aa0ce96b01892d74ec

[dmazzoni, 2016-10-10 18:58:05]

Description was changed from

==========
Merge to M54: Don't post events on internal nodes in the accessibility tree on
Android.

Sometimes we get events on nodes in the internal accessibility tree that
are not exposed on that platform or under all circumstances. On Android
that led to an issue where after closing a SELECT pop-up, we got a focus
event on the OPTION and subsequent navigation was trapped inside that
control rather than outside it.

The fix is to map the focus event to the topmost leaf ancestor, which
in this case would be the SELECT element.

BUG=652805

Review-Url: https://codereview.chromium.org/2397503002
Cr-Commit-Position: refs/heads/master@{#422944}
(cherry picked from commit 7969d3a5bcf2af3fac57c3acef518298e8c48382)
==========

to

==========
Merge to M54: Don't post events on internal nodes in the accessibility tree on
Android.

Sometimes we get events on nodes in the internal accessibility tree that
are not exposed on that platform or under all circumstances. On Android
that led to an issue where after closing a SELECT pop-up, we got a focus
event on the OPTION and subsequent navigation was trapped inside that
control rather than outside it.

The fix is to map the focus event to the topmost leaf ancestor, which
in this case would be the SELECT element.

BUG=652805

Review-Url: https://codereview.chromium.org/2397503002
Cr-Commit-Position: refs/heads/master@{#422944}
(cherry picked from commit 7969d3a5bcf2af3fac57c3acef518298e8c48382)

Committed:
https://chromium.googlesource.com/chromium/src/+/55a0dba38e5df7bea291c3aa0ce9...
==========

[dmazzoni, 2016-10-10 18:58:07]

Committed patchset #1 (id:1) manually as
55a0dba38e5df7bea291c3aa0ce96b01892d74ec.