Enabled/disable touch screen in TabletPowerButtonController

chrome/browser/chromeos/system/input_device_settings.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_SYSTEM_INPUT_DEVICE_SETTINGS_H_
 #define CHROME_BROWSER_CHROMEOS_SYSTEM_INPUT_DEVICE_SETTINGS_H_
 
 #include "base/callback.h"
 #include "base/logging.h"
 #include "chromeos/chromeos_export.h"
@@ skipping 163 matching lines @@
   // where other input devices like mouse are absent.
   static bool ForceKeyboardDrivenUINavigation();
 
   // Registers profile pref names for touchpad and touch screen statuses.
   static void RegisterProfilePrefs(PrefRegistrySimple* registry);
 
   // Updates the on/off status of the touchscreen/touchpad from the active
   // user's preferences.
   void UpdateTouchDevicesStatusFromActiveProfilePrefs();
 
-  // Toggles the status of Touchscreen/Touchpad on or off and updates the local
-  // prefs.
-  void ToggleTouchscreen();
+  // Returns true if touchscreen is on, otherwise false.
+  bool IsTouchscreenEnabled() const;
+
+  // Sets the status of touchscreen to |enabled| and updates the local prefs.
+  void SetTouchscreenEnabled(bool enabled);
+
+  // Toggles the status of Touchpad on or off and updates the local prefs.

[Daniel Erat, 2016/11/30 22:58:07]

nit: s/Touchpad/touchpad/

[Qiang(Joe) Xu, 2016/12/02 17:42:52]

Done.

   void ToggleTouchpad();
 
   // Calls |callback|, possibly asynchronously, after determining if a touchpad
   // is connected.
   virtual void TouchpadExists(const DeviceExistsCallback& callback) = 0;
 
   // Updates several touchpad settings at a time. Updates only settings that
   // are set in |settings| object. It is more efficient to use this method to
   // update several settings then calling Set* methods one by one.
   virtual void UpdateTouchpadSettings(const TouchpadSettings& settings) = 0;
@@ skipping 41 matching lines @@
 
  private:
   virtual void SetInternalTouchpadEnabled(bool enabled) {}
   virtual void SetTouchscreensEnabled(bool enabled) {}
 };
 
 }  // namespace system
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_SYSTEM_INPUT_DEVICE_SETTINGS_H_