Resuming from suspend should stop backlights forced off if they are

ash/system/chromeos/power/tablet_power_button_controller_unittest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/system/chromeos/power/tablet_power_button_controller.h"
 
 #include <memory>
 
 #include "ash/common/ash_switches.h"
 #include "ash/common/session/session_state_delegate.h"
@@ skipping 192 matching lines @@
 // Tests tapping power button when screen is idle off.
 TEST_F(TabletPowerButtonControllerTest, TappingPowerButtonWhenScreenIsIdleOff) {
   power_manager_client_->SendBrightnessChanged(0, false);
   PressPowerButton();
   EXPECT_FALSE(GetBacklightsForcedOff());
   power_manager_client_->SendBrightnessChanged(kNonZeroBrightness, false);
   ReleasePowerButton();
   EXPECT_FALSE(GetBacklightsForcedOff());
 }
 
-// Tests tapping power button when device is suspended.
-TEST_F(TabletPowerButtonControllerTest, TappingPowerButtonWhenSuspended) {
+// Tests tapping power button when device is suspended without backlights forced
+// off.
+TEST_F(TabletPowerButtonControllerTest,
+       TappingPowerButtonWhenSuspendedWithoutBacklightsForcedOff) {
   base::SimpleTestTickClock* tick_clock = new base::SimpleTestTickClock;
   // |tick_clock| owned by |tablet_controller_|.

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

nit: remove this comment; passing an std::unique_ptr makes it clear that
ownership is being transferred.

you might want to consider just making this a member and passing it in the base
class's SetUp method, since it's needed by multiple tests now.

   tablet_controller_->SetTickClockForTesting(
       std::unique_ptr<base::TickClock>(tick_clock));
 
   power_manager_client_->SendSuspendImminent();
   power_manager_client_->SendBrightnessChanged(0, false);
   // There is a power button pressed here, but PowerButtonEvent is sent later.
   power_manager_client_->SendSuspendDone();
   power_manager_client_->SendBrightnessChanged(kNonZeroBrightness, false);
 
   // Send the power button event after a short delay and check that it is
   // ignored.
   tick_clock->Advance(base::TimeDelta::FromMilliseconds(500));
   power_manager_client_->SendPowerButtonEvent(true, tick_clock->NowTicks());
   power_manager_client_->SendPowerButtonEvent(false, tick_clock->NowTicks());
   EXPECT_FALSE(GetBacklightsForcedOff());
 
   // Send the power button event after a longer delay and check that it is not
   // ignored.
   tick_clock->Advance(base::TimeDelta::FromMilliseconds(1600));
   power_manager_client_->SendPowerButtonEvent(true, tick_clock->NowTicks());
   power_manager_client_->SendPowerButtonEvent(false, tick_clock->NowTicks());
+  power_manager_client_->SendBrightnessChanged(0, false);
   EXPECT_TRUE(GetBacklightsForcedOff());
 }
 
+// Tests tapping power button when device is suspended with backlights forced
+// off.
+TEST_F(TabletPowerButtonControllerTest,
+       TappingPowerButtonWhenSuspendedWithBacklightsForcedOff) {
+  base::SimpleTestTickClock* tick_clock = new base::SimpleTestTickClock;
+  // |tick_clock| owned by |tablet_controller_|.

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

same here

+  tablet_controller_->SetTickClockForTesting(
+      std::unique_ptr<base::TickClock>(tick_clock));
+
+  PressPowerButton();
+  ReleasePowerButton();
+  power_manager_client_->SendBrightnessChanged(0, false);
+  EXPECT_TRUE(GetBacklightsForcedOff());
+  power_manager_client_->SendSuspendImminent();
+  // There is a power button pressed here, but PowerButtonEvent is sent later.
+  // Because of backlights forced off, resuming system will not resume

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

nit: s/will not resume/will not restore/

+  // brightness.
+  power_manager_client_->SendSuspendDone();
+
+  // Send the power button event after a short delay and check that it is
+  // ignored. But if backlights are forced off, stop forcing off.
+  tick_clock->Advance(base::TimeDelta::FromMilliseconds(500));
+  power_manager_client_->SendPowerButtonEvent(true, tick_clock->NowTicks());
+  power_manager_client_->SendBrightnessChanged(kNonZeroBrightness, false);
+  power_manager_client_->SendPowerButtonEvent(false, tick_clock->NowTicks());
+  EXPECT_FALSE(GetBacklightsForcedOff());
+
+  // Send the power button event after a longer delay and check that it is not
+  // ignored.
+  tick_clock->Advance(base::TimeDelta::FromMilliseconds(1600));
+  power_manager_client_->SendPowerButtonEvent(true, tick_clock->NowTicks());
+  power_manager_client_->SendPowerButtonEvent(false, tick_clock->NowTicks());
+  power_manager_client_->SendBrightnessChanged(0, false);
+  EXPECT_TRUE(GetBacklightsForcedOff());
+}
+
 // For convertible device working on laptop mode, tests keyboard/mouse event
 // when screen is off.
 TEST_F(TabletPowerButtonControllerTest, ConvertibleOnLaptopMode) {
   EnableMaximizeMode(false);
 
   // KeyEvent should SetBacklightsForcedOff(false).
   PressPowerButton();
   ReleasePowerButton();
   power_manager_client_->SendBrightnessChanged(0, false);
   EXPECT_TRUE(GetBacklightsForcedOff());
@@ skipping 67 matching lines @@
   tablet_controller_->OnKeyEvent(&power_key_pressed);
   tablet_controller_->OnKeyEvent(&power_key_pressed);
   ReleasePowerButton();
   tablet_controller_->OnKeyEvent(&power_key_released);
   tablet_controller_->OnKeyEvent(&power_key_released);
   EXPECT_EQ(1, power_manager_client_->num_set_backlights_forced_off_calls());
 }
 
 }  // namespace test
 }  // namespace ash