mash: Disable calls to suspend and resume displays.

mash: Disable calls to suspend and resume displays.

To avoid crashes when suspending or resuming, make
ash::PowerEventObserver skip calling
DisplayConfigurator::SuspendDisplays or ResumeDisplays when
running in mash. Once mus exposes this functionality, these
calls should go through it instead.

BUG=686938, 692193
Review-Url: https://codereview.chromium.org/2690263005
Cr-Commit-Position: refs/heads/master@{#450480}
Committed: https://chromium.googlesource.com/chromium/src/+/2b892c8633d4e17894340683093748d229dcd3e7

[Daniel Erat, 2017-02-14 20:10:33]

The CQ bit was checked by derat@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-02-14 20:11:16]

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

[Daniel Erat, 2017-02-14 20:15:11]

derat@chromium.org changed reviewers:
+ jamescook@chromium.org

[Daniel Erat, 2017-02-14 20:15:11]

this seems like the quickest path to avoid crashing during suspend/resume. i
looked into adding the needed functionality to the mus mojo interface, but i
think it may be quite involved due to the callbacks (we've had multiple bugs in
the past related to tricky sync vs. async behavior in DisplayConfigurator).

so, let me know if this seems okay. i suspect that this approach may not even
have any downsides at the moment, because i think that ResumeDisplays currently
just turns displays off for dark resume, which has been disabled for a while.

[James Cook, 2017-02-14 21:10:31]

LGTM. This seems reasonable.

https://codereview.chromium.org/2690263005/diff/1/ash/system/chromeos/power/p...
File ash/system/chromeos/power/power_event_observer.cc (right):

https://codereview.chromium.org/2690263005/diff/1/ash/system/chromeos/power/p...
ash/system/chromeos/power/power_event_observer.cc:94: if (!screen_locked_ &&
delegate->ShouldLockScreenAutomatically() &&
Just as an FYI, ShouldLockScreenAutomatically is always false on mus

https://cs.chromium.org/chromium/src/ash/mus/shell_delegate_mus.cc?type=cs&l=43

[commit-bot: I haz the power, 2017-02-14 21:11:38]

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

[commit-bot: I haz the power, 2017-02-14 21:11:40]

Dry run: This issue passed the CQ dry run.

[Daniel Erat, 2017-02-14 21:17:46]

https://codereview.chromium.org/2690263005/diff/1/ash/system/chromeos/power/p...
File ash/system/chromeos/power/power_event_observer.cc (right):

https://codereview.chromium.org/2690263005/diff/1/ash/system/chromeos/power/p...
ash/system/chromeos/power/power_event_observer.cc:94: if (!screen_locked_ &&
delegate->ShouldLockScreenAutomatically() &&
On 2017/02/14 21:10:31, James Cook wrote:
> Just as an FYI, ShouldLockScreenAutomatically is always false on mus
> 
>
https://cs.chromium.org/chromium/src/ash/mus/shell_delegate_mus.cc?type=cs&l=43

hmm, is that going to be a problem for the 30-minute-browser use case? this
means that we won't lock the screen when the lid is closed, which will be
surprising for users who have "require password to wake from sleep" enabled...
or whose organizations have enabled that setting.

maybe this is blocked on "get screen-lock working" in any case, though.

[Daniel Erat, 2017-02-14 21:17:53]

The CQ bit was checked by derat@chromium.org

[commit-bot: I haz the power, 2017-02-14 21:18:27]

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, 2017-02-14 21:25:26]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1487107073157520, "parent_rev":
"733d09b5b7c0edd6e59d10e9e9d7a7fd81ab3509", "commit_rev":
"2b892c8633d4e17894340683093748d229dcd3e7"}

[commit-bot: I haz the power, 2017-02-14 21:26:04]

Description was changed from

==========
mash: Disable calls to suspend and resume displays.

To avoid crashes when suspending or resuming, make
ash::PowerEventObserver skip calling
DisplayConfigurator::SuspendDisplays or ResumeDisplays when
running in mash. Once mus exposes this functionality, these
calls should go through it instead.

BUG=686938,692193
==========

to

==========
mash: Disable calls to suspend and resume displays.

To avoid crashes when suspending or resuming, make
ash::PowerEventObserver skip calling
DisplayConfigurator::SuspendDisplays or ResumeDisplays when
running in mash. Once mus exposes this functionality, these
calls should go through it instead.

BUG=686938,692193

Review-Url: https://codereview.chromium.org/2690263005
Cr-Commit-Position: refs/heads/master@{#450480}
Committed:
https://chromium.googlesource.com/chromium/src/+/2b892c8633d4e178943406830937...
==========

[commit-bot: I haz the power, 2017-02-14 21:26:05]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/2b892c8633d4e178943406830937...