Reland of Uses the activedescendant_changed event received from Blink to fire the right focus event

Reland of Uses the activedescendant_changed event received from Blink to fire the right focus event (patchset #1 id:1 of https://codereview.chromium.org/2024053003/ )

Reason for revert:
Tests will be disabled on a different CL to keep track of fixing them.

Original issue's description:
> Revert of Uses the activedescendant_changed event received from Blink to fire the right focus event (patchset #15 id:280001 of https://codereview.chromium.org/1899823002/ )
>
> Reason for revert:
> After this CL, DumpAccessibilityEventsTest.AccessibilityEventsAriaComboBoxFocus started to fail consistently on the Mac 10.11 Tests bot.
> https://build.chromium.org/p/chromium.mac/builders/Mac10.11%20Tests/builds/1737
>
> Original issue's description:
> > Uses the activedescendant_changed event received from Blink to fire the right focus event on the browser side.
> >
> > 1. Changed all <select> based widgets (list box role and menu list popup role) to fire activedescendant_changed events when the current selection changes. This behavior is the same as with ARIA combo boxes and other ARIA-based widgets that can have an active descendant. This means that we now have a uniform way of notifying the browser when the active child of a widget has changed.
> > 2. Modified platform-specific code to fire the focus events on the active descendant when it changes, instead of relying on Blink.
> > 3. Fires a focus event on the whole list or combo box when it collapses to make Windows screen readers enable their virtual cursor again.
> > BUG=593646
> > R=dmazzoni@chromium.org
> > TESTED=Jaws NVDA and VoiceOver, browser tests
> >
> > Committed: https://crrev.com/2c4ec4bed7e28e4f45efe742833dd3a154ac266b
> > Cr-Commit-Position: refs/heads/master@{#396653}
>
> TBR=dmazzoni@chromium.org,nektar@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=593646
>
> Committed: https://crrev.com/292b41bbd603ae2f11d239f457a8a5f04387fa85
> Cr-Commit-Position: refs/heads/master@{#396830}

TBR=dmazzoni@chromium.org,guidou@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=593646
Committed: https://crrev.com/f6c9ef029e28a6bef28e727cd70751d782963e21
Cr-Commit-Position: refs/heads/master@{#396833}

[nektarios, 2016-05-31 15:49:03]

The CQ bit was checked by nektar@chromium.org

[nektarios, 2016-05-31 15:49:04]

Created Reland of Uses the activedescendant_changed event received from Blink to
fire the right focus event

[commit-bot: I haz the power, 2016-05-31 15:49:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2025923002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/2025923002/1

[commit-bot: I haz the power, 2016-05-31 15:50:31]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-05-31 15:52:03]

Description was changed from

==========
Reland of Uses the activedescendant_changed event received from Blink to fire
the right focus event (patchset #1 id:1 of
https://codereview.chromium.org/2024053003/ )

Reason for revert:
Tests will be disabled on a different CL to keep track of fixing them.

Original issue's description:
> Revert of Uses the activedescendant_changed event received from Blink to fire
the right focus event (patchset #15 id:280001 of
https://codereview.chromium.org/1899823002/ )
> 
> Reason for revert:
> After this CL,
DumpAccessibilityEventsTest.AccessibilityEventsAriaComboBoxFocus started to fail
consistently on the Mac 10.11 Tests bot.
>
https://build.chromium.org/p/chromium.mac/builders/Mac10.11%20Tests/builds/1737
> 
> Original issue's description:
> > Uses the activedescendant_changed event received from Blink to fire the
right focus event on the browser side.
> >
> > 1. Changed all <select> based widgets (list box role and menu list popup
role) to fire activedescendant_changed events when the current selection
changes. This behavior is the same as with ARIA combo boxes and other ARIA-based
widgets that can have an active descendant. This means that we now have a
uniform way of notifying the browser when the active child of a widget has
changed.
> > 2. Modified platform-specific code to fire the focus events on the active
descendant when it changes, instead of relying on Blink.
> > 3. Fires a focus event on the whole list or combo box when it collapses to
make Windows screen readers enable their virtual cursor again.
> > BUG=593646
> > R=dmazzoni@chromium.org
> > TESTED=Jaws NVDA and VoiceOver, browser tests
> >
> > Committed: https://crrev.com/2c4ec4bed7e28e4f45efe742833dd3a154ac266b
> > Cr-Commit-Position: refs/heads/master@{#396653}
> 
> TBR=dmazzoni@chromium.org,nektar@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=593646
> 
> Committed: https://crrev.com/292b41bbd603ae2f11d239f457a8a5f04387fa85
> Cr-Commit-Position: refs/heads/master@{#396830}

TBR=dmazzoni@chromium.org,guidou@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=593646
==========

to

==========
Reland of Uses the activedescendant_changed event received from Blink to fire
the right focus event (patchset #1 id:1 of
https://codereview.chromium.org/2024053003/ )

Reason for revert:
Tests will be disabled on a different CL to keep track of fixing them.

Original issue's description:
> Revert of Uses the activedescendant_changed event received from Blink to fire
the right focus event (patchset #15 id:280001 of
https://codereview.chromium.org/1899823002/ )
>
> Reason for revert:
> After this CL,
DumpAccessibilityEventsTest.AccessibilityEventsAriaComboBoxFocus started to fail
consistently on the Mac 10.11 Tests bot.
>
https://build.chromium.org/p/chromium.mac/builders/Mac10.11%20Tests/builds/1737
>
> Original issue's description:
> > Uses the activedescendant_changed event received from Blink to fire the
right focus event on the browser side.
> >
> > 1. Changed all <select> based widgets (list box role and menu list popup
role) to fire activedescendant_changed events when the current selection
changes. This behavior is the same as with ARIA combo boxes and other ARIA-based
widgets that can have an active descendant. This means that we now have a
uniform way of notifying the browser when the active child of a widget has
changed.
> > 2. Modified platform-specific code to fire the focus events on the active
descendant when it changes, instead of relying on Blink.
> > 3. Fires a focus event on the whole list or combo box when it collapses to
make Windows screen readers enable their virtual cursor again.
> > BUG=593646
> > R=dmazzoni@chromium.org
> > TESTED=Jaws NVDA and VoiceOver, browser tests
> >
> > Committed: https://crrev.com/2c4ec4bed7e28e4f45efe742833dd3a154ac266b
> > Cr-Commit-Position: refs/heads/master@{#396653}
>
> TBR=dmazzoni@chromium.org,nektar@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=593646
>
> Committed: https://crrev.com/292b41bbd603ae2f11d239f457a8a5f04387fa85
> Cr-Commit-Position: refs/heads/master@{#396830}

TBR=dmazzoni@chromium.org,guidou@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=593646

Committed: https://crrev.com/f6c9ef029e28a6bef28e727cd70751d782963e21
Cr-Commit-Position: refs/heads/master@{#396833}
==========

[commit-bot: I haz the power, 2016-05-31 15:52:04]

Patchset 1 (id:??) landed as
https://crrev.com/f6c9ef029e28a6bef28e727cd70751d782963e21
Cr-Commit-Position: refs/heads/master@{#396833}