Added quick lock mechanism while in Touchview

ash/wm/power_button_controller.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 ASH_WM_POWER_BUTTON_CONTROLLER_H_
 #define ASH_WM_POWER_BUTTON_CONTROLLER_H_
 
+#include "ash/accelerators/accelerator_controller.h"
+#include "ash/accelerators/accelerator_table.h"
 #include "ash/ash_export.h"
 #include "ash/wm/session_state_animator.h"
 #include "base/basictypes.h"
+#include "ui/base/accelerators/accelerator.h"
 
 #if defined(OS_CHROMEOS)
 #include "ui/display/chromeos/display_configurator.h"
 #endif
 
 namespace gfx {
 class Rect;
 class Size;
 }
 
 namespace ui {
 class Layer;
 }
 
 namespace ash {
 
 namespace test {
 class PowerButtonControllerTest;
 }
 
 class LockStateController;
 
-// Displays onscreen animations and locks or suspends the system in response to
-// the power button being pressed or released.
+// Handles power & lock button events which may result in the locking or
+// shutting down of the system as well as taking screen shots.
 class ASH_EXPORT PowerButtonController
+    : ui::EventHandler
 // TODO(derat): Remove these ifdefs after DisplayConfigurator becomes
 // cross-platform.
 #if defined(OS_CHROMEOS)
-    : public ui::DisplayConfigurator::Observer
+      , public ui::DisplayConfigurator::Observer
 #endif
       {
  public:
   explicit PowerButtonController(LockStateController* controller);
   virtual ~PowerButtonController();
 
   void set_has_legacy_power_button_for_test(bool legacy) {
     has_legacy_power_button_ = legacy;
   }
 
+  void set_enable_quick_lock_for_test(bool enable_quick_lock) {
+    enable_quick_lock_ = enable_quick_lock;
+  }
+
   // Called when the current screen brightness changes.
   void OnScreenBrightnessChanged(double percent);
 
   // Called when the power or lock buttons are pressed or released.
   void OnPowerButtonEvent(bool down, const base::TimeTicks& timestamp);
   void OnLockButtonEvent(bool down, const base::TimeTicks& timestamp);
 
+  // ui::EventHandler:
+  virtual void OnKeyEvent(ui::KeyEvent* event) OVERRIDE;
+
 #if defined(OS_CHROMEOS)
   // Overriden from ui::DisplayConfigurator::Observer:
   virtual void OnDisplayModeChanged(
       const ui::DisplayConfigurator::DisplayStateList& outputs) OVERRIDE;
 #endif
 
  private:
   friend class test::PowerButtonControllerTest;
 
   // Are the power or lock buttons currently held?
   bool power_button_down_;
   bool lock_button_down_;
 
+  // True when the volume down button is being held down.
+  bool volume_down_pressed_;
+
   // Has the screen brightness been reduced to 0%?
   bool brightness_is_zero_;
 
   // True if an internal display is off while an external display is on (e.g.
   // for Chrome OS's docked mode, where a Chromebook's lid is closed while an
   // external display is connected).
   bool internal_display_off_and_external_display_on_;
 
   // Was a command-line switch set telling us that we're running on hardware
   // that misreports power button releases?
   bool has_legacy_power_button_;
 
-  LockStateController* controller_; // Not owned.
+  // Enables quick, non-cancellable locking of the screen when in maximize mode.
+  bool enable_quick_lock_;
+
+  LockStateController* controller_;  // Not owned.
 
   DISALLOW_COPY_AND_ASSIGN(PowerButtonController);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_POWER_BUTTON_CONTROLLER_H_