Revert of Re-land: Fix loading accessibility tree for child frame that's already loaded.

Revert of Re-land: Fix loading accessibility tree for child frame that's already loaded. (patchset #1 id:1 of https://codereview.chromium.org/2299283002/ )

Reason for revert:
Leads to a lot of try flakes / flakes in general:

Original issue's description:
> Re-land: Fix loading accessibility tree for child frame that's already loaded.
>
> (Original issue: http://crrev.com/2299673002 - fixed test failures on Mac
> by disabling accessibility between subsequent runs.)
>
> Code leftover from the pre-OOPIF days was causing us to exit early from
> the RenderAccessibilityImpl constructor for some child frames that were
> already loaded. Everything worked fine if accessibility was already enabled
> when loading the frame, but if the frame was already loaded and then
> accessibility was enabled, this could cause it to fail to create an
> accessibility tree.
>
> The code in RenderAccessibilityImpl is no longer needed because now we
> have exactly one accessibility tree per frame.
>
> This wasn't caught by tests because we didn't cover both scenarios, we
> always enabled accessibility first.
>
> Added two variants of existing tests that load the page first and then
> enable accessibility.
>
> BUG=640231
> TBR=dtseng@chromium.org
>
> Committed: https://crrev.com/e3d6283c33ce68650657647a842f21eaacb15cd8
> Cr-Commit-Position: refs/heads/master@{#416274}

TBR=dtseng@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=640231
Committed: https://crrev.com/dcb4915ac03bb8ce123975fd1bead718410d0a70
Cr-Commit-Position: refs/heads/master@{#416363}

[dmazzoni, 2016-09-02 22:08:09]

The CQ bit was checked by dmazzoni@chromium.org

[dmazzoni, 2016-09-02 22:08:09]

Created Revert of Re-land: Fix loading accessibility tree for child frame that's
already loaded.

[commit-bot: I haz the power, 2016-09-02 22:08:46]

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, 2016-09-02 22:10:16]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-09-02 22:12:03]

Description was changed from

==========
Revert of Re-land: Fix loading accessibility tree for child frame that's already
loaded. (patchset #1 id:1 of https://codereview.chromium.org/2299283002/ )

Reason for revert:
Leads to a lot of try flakes / flakes in general:




Original issue's description:
> Re-land: Fix loading accessibility tree for child frame that's already loaded.
> 
> (Original issue: http://crrev.com/2299673002 - fixed test failures on Mac
> by disabling accessibility between subsequent runs.)
> 
> Code leftover from the pre-OOPIF days was causing us to exit early from
> the RenderAccessibilityImpl constructor for some child frames that were
> already loaded. Everything worked fine if accessibility was already enabled
> when loading the frame, but if the frame was already loaded and then
> accessibility was enabled, this could cause it to fail to create an
> accessibility tree.
> 
> The code in RenderAccessibilityImpl is no longer needed because now we
> have exactly one accessibility tree per frame.
> 
> This wasn't caught by tests because we didn't cover both scenarios, we
> always enabled accessibility first.
> 
> Added two variants of existing tests that load the page first and then
> enable accessibility.
> 
> BUG=640231
> TBR=dtseng@chromium.org
> 
> Committed: https://crrev.com/e3d6283c33ce68650657647a842f21eaacb15cd8
> Cr-Commit-Position: refs/heads/master@{#416274}

TBR=dtseng@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=640231
==========

to

==========
Revert of Re-land: Fix loading accessibility tree for child frame that's already
loaded. (patchset #1 id:1 of https://codereview.chromium.org/2299283002/ )

Reason for revert:
Leads to a lot of try flakes / flakes in general:

Original issue's description:
> Re-land: Fix loading accessibility tree for child frame that's already loaded.
>
> (Original issue: http://crrev.com/2299673002 - fixed test failures on Mac
> by disabling accessibility between subsequent runs.)
>
> Code leftover from the pre-OOPIF days was causing us to exit early from
> the RenderAccessibilityImpl constructor for some child frames that were
> already loaded. Everything worked fine if accessibility was already enabled
> when loading the frame, but if the frame was already loaded and then
> accessibility was enabled, this could cause it to fail to create an
> accessibility tree.
>
> The code in RenderAccessibilityImpl is no longer needed because now we
> have exactly one accessibility tree per frame.
>
> This wasn't caught by tests because we didn't cover both scenarios, we
> always enabled accessibility first.
>
> Added two variants of existing tests that load the page first and then
> enable accessibility.
>
> BUG=640231
> TBR=dtseng@chromium.org
>
> Committed: https://crrev.com/e3d6283c33ce68650657647a842f21eaacb15cd8
> Cr-Commit-Position: refs/heads/master@{#416274}

TBR=dtseng@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=640231

Committed: https://crrev.com/dcb4915ac03bb8ce123975fd1bead718410d0a70
Cr-Commit-Position: refs/heads/master@{#416363}
==========

[commit-bot: I haz the power, 2016-09-02 22:12:04]

Patchset 1 (id:??) landed as
https://crrev.com/dcb4915ac03bb8ce123975fd1bead718410d0a70
Cr-Commit-Position: refs/heads/master@{#416363}