cros: Update touchscreen status with backlights forced off state during start

ash/system/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/power/tablet_power_button_controller.h"
 
 #include <memory>
 
 #include "ash/ash_switches.h"
 #include "ash/public/cpp/config.h"
@@ skipping 489 matching lines @@
   PressPowerButton();
   ReleasePowerButton();
   ASSERT_TRUE(GetBacklightsForcedOff());
 
   // A lid open event is received, we should stop forcing off backlights.
   power_manager_client_->SetLidState(
       chromeos::PowerManagerClient::LidState::OPEN, tick_clock_->NowTicks());
   EXPECT_FALSE(GetBacklightsForcedOff());
 }
 
+// Tests that with system reboot, the local state of touchscreen enabled state
+// should be synced with new backlights forced off state from powerd.
+TEST_F(TabletPowerButtonControllerTest, SyncTouchscreenStatus) {
+  shell_delegate_->SetTouchscreenEnabledInPrefs(false,
+                                                true /* use_local_state */);
+  ASSERT_FALSE(shell_delegate_->IsTouchscreenEnabledInPrefs(true));
+
+  // Simulate system reboot by resetting backlights forced off state in powerd
+  // and TabletPowerButtonController.
+  power_manager_client_->SetBacklightsForcedOff(false);
+  Shell::Get()
+      ->power_button_controller()
+      ->ResetTabletPowerButtonControllerForTest();
+
+  // Check that the local state of touchscreen enabled state is in line with
+  // backlights forced off state.
+  EXPECT_FALSE(GetBacklightsForcedOff());
+  EXPECT_TRUE(shell_delegate_->IsTouchscreenEnabledInPrefs(true));
+}
+
 }  // namespace test
 }  // namespace ash