Resuming from suspend should stop backlights forced off if they are

ash/system/chromeos/power/tablet_power_button_controller.cc

Index: ash/system/chromeos/power/tablet_power_button_controller.cc
diff --git a/ash/system/chromeos/power/tablet_power_button_controller.cc b/ash/system/chromeos/power/tablet_power_button_controller.cc
index 06d9efae2292990d999ea471bae6c94bf3424912..9b8a2cb5823fdcac8b3dc0e4d9140efb5b452683 100644
--- a/ash/system/chromeos/power/tablet_power_button_controller.cc
+++ b/ash/system/chromeos/power/tablet_power_button_controller.cc
@@ -94,10 +94,14 @@ void TabletPowerButtonController::OnPowerButtonEvent(
   // When the system resumes in response to the power button being pressed,
   // Chrome receives powerd's SuspendDone signal and notification that the
   // backlight has been turned back on before seeing the power button events
-  // that woke the system. Ignore events just after resuming to ensure that we
-  // don't turn the screen off in response to the events.
+  // that woke the system. If backlights are forced off, stop forcing off

[Daniel Erat, 2016/12/02 00:58:27]

nit: i'd move this "If ..." part down just before the "if (down &&
backlights_forced_off_)" line, since that's what it's referring to.

+  // because resuming system doesn't handle this, otherwise ignore events
+  // just after resuming to ensure that we don't turn the screen off in response
+  // to the events.
   if (timestamp - last_resume_time_ <=
       base::TimeDelta::FromMilliseconds(kIgnorePowerButtonAfterResumeMs)) {
+    if (down && backlights_forced_off_)
+      SetBacklightsForcedOff(false);

[Qiang(Joe) Xu, 2016/12/02 01:06:38]

Hi, just want to mention here, the long pressed shutdown white animation is
missing here because the following StartShutdownTimer is ignored. I need to
think of fixing it. It can be fixed within this cl or separately.

[Daniel Erat, 2016/12/02 01:10:26]

are you just saying power button down events that wake the system from suspend
won't trigger shutdown? i think that that's the correct behavior, actually. the
non-tablet power button controller does something similar: we don't lock or shut
down when the power button is pressed while the screen is off.

     return;
   }