Perform a display configuration in software mirror on hotplug event

Perform a display configuration in software mirror on hotplug event

On a hotplug event we configure the displays regardless of the state.
However if we're in software mirror mode the configuration was skipped
if the previous configuration was extended mode.

We want to have a consistent approach to display configuration, so make
sure we configure the displays if the configuration was triggered by a
system event. Otherwise (if the configuration was requested by the user)
we'll just skip the configuration so we don't perform unnecessary
modesets.

BUG=488736
Committed: https://crrev.com/1559e6b945b7c0d24c6d3f79a6c6dd811690fc4c
Cr-Commit-Position: refs/heads/master@{#330534}

[dnicoara, 2015-05-19 16:25:53]

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

[commit-bot: I haz the power, 2015-05-19 16:26:45]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1133743005/1

[dnicoara, 2015-05-19 16:27:16]

dnicoara@chromium.org changed reviewers:
+ oshima@chromium.org

[oshima, 2015-05-19 16:42:28]

lgtm

https://codereview.chromium.org/1133743005/diff/1/ui/display/chromeos/update_...
File ui/display/chromeos/update_display_configuration_task_unittest.cc (right):

https://codereview.chromium.org/1133743005/diff/1/ui/display/chromeos/update_...
ui/display/chromeos/update_display_configuration_task_unittest.cc:28: bool
SoftwareMirroringEnabled() const override { return is_enabled_; }
optional: accessors/mutators are typically uses set_variable_name(),
variable_name().

[oshima, 2015-05-19 16:42:54]

https://codereview.chromium.org/1133743005/diff/1/ui/display/chromeos/update_...
File ui/display/chromeos/update_display_configuration_task_unittest.cc (right):

https://codereview.chromium.org/1133743005/diff/1/ui/display/chromeos/update_...
ui/display/chromeos/update_display_configuration_task_unittest.cc:28: bool
SoftwareMirroringEnabled() const override { return is_enabled_; }
On 2015/05/19 16:42:28, oshima wrote:
> optional: accessors/mutators are typically uses set_variable_name(),
> variable_name().

Doh, s/uses//

[dnicoara, 2015-05-19 16:50:16]

https://codereview.chromium.org/1133743005/diff/1/ui/display/chromeos/update_...
File ui/display/chromeos/update_display_configuration_task_unittest.cc (right):

https://codereview.chromium.org/1133743005/diff/1/ui/display/chromeos/update_...
ui/display/chromeos/update_display_configuration_task_unittest.cc:28: bool
SoftwareMirroringEnabled() const override { return is_enabled_; }
On 2015/05/19 16:42:28, oshima wrote:
> optional: accessors/mutators are typically uses set_variable_name(),
> variable_name().

I know, but these are part of an interface, so they need to follow a different
convention.

[oshima, 2015-05-19 16:53:52]

https://codereview.chromium.org/1133743005/diff/1/ui/display/chromeos/update_...
File ui/display/chromeos/update_display_configuration_task_unittest.cc (right):

https://codereview.chromium.org/1133743005/diff/1/ui/display/chromeos/update_...
ui/display/chromeos/update_display_configuration_task_unittest.cc:28: bool
SoftwareMirroringEnabled() const override { return is_enabled_; }
On 2015/05/19 16:50:16, dnicoara wrote:
> On 2015/05/19 16:42:28, oshima wrote:
> > optional: accessors/mutators are typically uses set_variable_name(),
> > variable_name().
> 
> I know, but these are part of an interface, so they need to follow a different
> convention.

sorry I missed override.

[commit-bot: I haz the power, 2015-05-19 16:59:52]

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

[commit-bot: I haz the power, 2015-05-19 16:59:53]

Dry run: This issue passed the CQ dry run.

[dnicoara, 2015-05-19 17:02:53]

The CQ bit was checked by dnicoara@chromium.org

[commit-bot: I haz the power, 2015-05-19 17:06:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1133743005/1

[commit-bot: I haz the power, 2015-05-19 17:12:20]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-19 17:14:50]

Patchset 1 (id:??) landed as
https://crrev.com/1559e6b945b7c0d24c6d3f79a6c6dd811690fc4c
Cr-Commit-Position: refs/heads/master@{#330534}