Hook up TABLET_MODE switch to maximize_mode_controller

ash/wm/maximize_mode/maximize_mode_controller.h

 // Copyright 2014 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 ASH_WM_MAXIMIZE_MODE_MAXIMIZE_MODE_CONTROLLER_H_
 #define ASH_WM_MAXIMIZE_MODE_MAXIMIZE_MODE_CONTROLLER_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
@@ skipping 75 matching lines @@
   // WindowTreeHostManager::Observer:
   void OnDisplayConfigurationChanged() override;
 
 #if defined(OS_CHROMEOS)
   // chromeos::AccelerometerReader::Observer:
   void OnAccelerometerUpdated(
       scoped_refptr<const chromeos::AccelerometerUpdate> update) override;
 
   // PowerManagerClient::Observer:
   void LidEventReceived(bool open, const base::TimeTicks& time) override;
+  void TabletModeEventReceived(bool on, const base::TimeTicks& time) override;
   void SuspendImminent() override;
   void SuspendDone(const base::TimeDelta& sleep_duration) override;
 #endif  // OS_CHROMEOS
 
  private:
   friend class MaximizeModeControllerTest;
   friend class MaximizeModeWindowManagerTest;
   friend class test::MultiUserWindowManagerChromeOSTest;
   friend class test::VirtualKeyboardControllerTest;
 
@@ skipping 56 matching lines @@
   base::TimeDelta total_non_touchview_time_;
 
   // Tracks the last time we received a lid open event. This is used to suppress
   // erroneous accelerometer readings as the lid is opened but the accelerometer
   // reports readings that make the lid to appear near fully open.
   base::TimeTicks last_lid_open_time_;
 
   // Source for the current time in base::TimeTicks.
   std::unique_ptr<base::TickClock> tick_clock_;
 
+#if defined(OS_CHROMEOS)
+  // Set when tablet mode switch transitions from on to off. This is used to
+  // make HandleHingeRotation check whether we need to disable maximize mode.
+  bool tablet_mode_switch_was_on_;

[Daniel Erat, 2016/06/06 15:24:55]

it would probably be better to track "is_on" instead of "was_on". using
temporarily-set member variables to pass state from one method to another is
confusing: someone looking at the member has no idea *when* the switch was on.

[jcliang, 2016/06/06 16:48:36]

Yes I agree. This is improved after we remove lid_open_past_180_.

+#endif
+
   // Tracks when the lid is closed. Used to prevent entering maximize mode.
   bool lid_is_closed_;
 
   // Tracks smoothed accelerometer data over time. This is done when the hinge
   // is approaching vertical to remove abrupt acceleration that can lead to
   // incorrect calculations of hinge angles.
   gfx::Vector3dF base_smoothed_;
   gfx::Vector3dF lid_smoothed_;
 
   DISALLOW_COPY_AND_ASSIGN(MaximizeModeController);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_MAXIMIZE_MODE_MAXIMIZE_MODE_CONTROLLER_H_