Unify and change logout/sleep/lock shortcuts

This CL implements an exit warning and requires the user to hold
the exit shortcut for a while, before actually exiting. This is
to prevent accidental exits due shortcut mistakes.

Expert user can exit quickly with a double press.

This is a second CL on this topic (see crrev.com/200204). The first
had issues by relying on release events, which this CL does not.

BUG=225903
R=sky@chromium.org
TEST=manual
out/Debug/ash_unittests --gtest_filter='AcceleratorControllerTest.ExitWarningHandlerTest*'

Review URL: https://chromiumcodereview.appspot.com/14771027

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@200957 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 143 insertions, 113 deletions

diff --git a/ash/accelerators/accelerator_controller.cc b/ash/accelerators/accelerator_controller.cc
index 43e2dac..175c79d 100644
--- a/ash/accelerators/accelerator_controller.cc
+++ b/ash/accelerators/accelerator_controller.cc
@@ -368,7 +368,8 @@ void AcceleratorControllerContext::UpdateContext(
 // AcceleratorController, public:
 
 AcceleratorController::AcceleratorController()
-    : accelerator_manager_(new ui::AcceleratorManager) {
+    : accelerator_manager_(new ui::AcceleratorManager),
+      exit_warning_handler_(&context_) {
   Init();
 }
 
@@ -577,9 +578,8 @@ bool AcceleratorController::PerformAction(int action,
     case OPEN_FEEDBACK_PAGE:
       ash::Shell::GetInstance()->delegate()->OpenFeedbackPage();
       return true;
-    case EXIT_PRESSED:
-    case EXIT_RELEASED:
-      exit_warning_handler_.HandleExitKey(action == EXIT_PRESSED);
+    case EXIT:
+      exit_warning_handler_.HandleAccelerator();
       return true;
     case NEW_INCOGNITO_WINDOW:
       Shell::GetInstance()->delegate()->NewWindow(true /* is_incognito */);
diff --git a/ash/accelerators/accelerator_controller.h b/ash/accelerators/accelerator_controller.h
index b1e4bfc..61076e6 100644
--- a/ash/accelerators/accelerator_controller.h
+++ b/ash/accelerators/accelerator_controller.h
@@ -41,6 +41,9 @@ class ASH_EXPORT AcceleratorControllerContext {
   // event type of the previous accelerator.
   void UpdateContext(const ui::Accelerator& accelerator);
 
+  const ui::Accelerator& current_accelerator() const {
+    return current_accelerator_;
+  }
   const ui::Accelerator& previous_accelerator() const {
     return previous_accelerator_;
   }
@@ -141,7 +144,6 @@ class ASH_EXPORT AcceleratorController : public ui::AcceleratorTarget {
   // TODO(derat): BrightnessControlDelegate is also used by the system tray;
   // move it outside of this class.
   scoped_ptr<BrightnessControlDelegate> brightness_control_delegate_;
-  ExitWarningHandler exit_warning_handler_;
   scoped_ptr<ImeControlDelegate> ime_control_delegate_;
   scoped_ptr<KeyboardBrightnessControlDelegate>
       keyboard_brightness_control_delegate_;
@@ -150,6 +152,10 @@ class ASH_EXPORT AcceleratorController : public ui::AcceleratorTarget {
   // Contextual information, eg. if the current accelerator is repeated.
   AcceleratorControllerContext context_;
 
+  // Handles the exit accelerator which requires a long hold to exit and
+  // shows a popup with an explanation.
+  ExitWarningHandler exit_warning_handler_;
+
   // A map from accelerators to the AcceleratorAction values, which are used in
   // the implementation.
   std::map<ui::Accelerator, int> accelerators_;
diff --git a/ash/accelerators/accelerator_controller_unittest.cc b/ash/accelerators/accelerator_controller_unittest.cc
index 933d0a5..216dbb5 100644
--- a/ash/accelerators/accelerator_controller_unittest.cc
+++ b/ash/accelerators/accelerator_controller_unittest.cc
@@ -322,23 +322,26 @@ class AcceleratorControllerTest : public test::AshTestBase {
   static bool ProcessWithContext(const ui::Accelerator& accelerator);
 
   // Several functions to access ExitWarningHandler (as friend).
-  static void StubForTest(ExitWarningHandler& ewh) {
-    ewh.stub_timers_for_test_ = true;
+  static void StubForTest(ExitWarningHandler* ewh) {
+    ewh->stub_timers_for_test_ = true;
   }
-  static void SimulateTimer1Expired(ExitWarningHandler& ewh) {
-    ewh.Timer1Action();
+  static void Reset(ExitWarningHandler* ewh) {
+    ewh->state_ = ExitWarningHandler::IDLE;
   }
-  static void SimulateTimer2Expired(ExitWarningHandler& ewh) {
-    ewh.Timer2Action();
+  static void SimulateTimer1Expired(ExitWarningHandler* ewh) {
+    ewh->Timer1Action();
   }
-  static bool is_ui_shown(ExitWarningHandler& ewh) {
-    return !!ewh.widget_;
+  static void SimulateTimer2Expired(ExitWarningHandler* ewh) {
+    ewh->Timer2Action();
   }
-  static bool is_idle(ExitWarningHandler& ewh) {
-    return ewh.state_ == ExitWarningHandler::IDLE;
+  static bool is_ui_shown(ExitWarningHandler* ewh) {
+    return !!ewh->widget_;
   }
-  static bool is_exiting(ExitWarningHandler& ewh) {
-    return ewh.state_ == ExitWarningHandler::EXITING;
+  static bool is_idle(ExitWarningHandler* ewh) {
+    return ewh->state_ == ExitWarningHandler::IDLE;
+  }
+  static bool is_exiting(ExitWarningHandler* ewh) {
+    return ewh->state_ == ExitWarningHandler::EXITING;
   }
 
  private:
@@ -356,71 +359,87 @@ bool AcceleratorControllerTest::ProcessWithContext(
   return controller->Process(accelerator);
 }
 
-// Quick double press of exit key => exiting
+#if !defined(OS_WIN)
+// Quick double press of exit shortcut => exiting
 TEST_F(AcceleratorControllerTest, ExitWarningHandlerTestDoublePress) {
-  ExitWarningHandler ewh;
+  ui::Accelerator press(ui::VKEY_Q, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN);
+  ui::Accelerator release(press);
+  release.set_type(ui::ET_KEY_RELEASED);
+  ExitWarningHandler* ewh = GetController()->GetExitWarningHandlerForTest();
+  ASSERT_TRUE(!!ewh);
   StubForTest(ewh);
   EXPECT_TRUE(is_idle(ewh));
   EXPECT_FALSE(is_ui_shown(ewh));
-
-  ewh.HandleExitKey(true);
+  EXPECT_TRUE(ProcessWithContext(press));
+  EXPECT_FALSE(ProcessWithContext(release));
   EXPECT_TRUE(is_ui_shown(ewh));
-  ewh.HandleExitKey(false);
-  ewh.HandleExitKey(true); // double press
+  EXPECT_TRUE(ProcessWithContext(press)); // double press
+  EXPECT_FALSE(ProcessWithContext(release));
   SimulateTimer1Expired(ewh); // simulate double press timer expired
   SimulateTimer2Expired(ewh); // simulate long hold timer expired
-  ewh.HandleExitKey(false);
   EXPECT_FALSE(is_ui_shown(ewh));
   EXPECT_TRUE(is_exiting(ewh));
+  Reset(ewh);
 }
 
-// Long hold of exit key => exiting
+// Long hold of exit shortcut => exiting
 TEST_F(AcceleratorControllerTest, ExitWarningHandlerTestLongHold) {
-  ExitWarningHandler ewh;
+  ui::Accelerator press(ui::VKEY_Q, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN);
+  ExitWarningHandler* ewh = GetController()->GetExitWarningHandlerForTest();
+  ASSERT_TRUE(!!ewh);
   StubForTest(ewh);
   EXPECT_TRUE(is_idle(ewh));
   EXPECT_FALSE(is_ui_shown(ewh));
-
-  ewh.HandleExitKey(true);
+  EXPECT_TRUE(ProcessWithContext(press)); // hold
   EXPECT_TRUE(is_ui_shown(ewh));
   SimulateTimer1Expired(ewh); // simulate double press timer expired
   SimulateTimer2Expired(ewh); // simulate long hold timer expired
-  ewh.HandleExitKey(false); // release after long hold
   EXPECT_FALSE(is_ui_shown(ewh));
   EXPECT_TRUE(is_exiting(ewh));
+  Reset(ewh);
 }
 
-// Release of exit key before hold time limit => cancel
+// Release of exit shortcut before hold time limit => cancel
 TEST_F(AcceleratorControllerTest, ExitWarningHandlerTestEarlyRelease) {
-  ExitWarningHandler ewh;
+  ui::Accelerator press(ui::VKEY_Q, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN);
+  ui::Accelerator release(press);
+  release.set_type(ui::ET_KEY_RELEASED);
+  ExitWarningHandler* ewh = GetController()->GetExitWarningHandlerForTest();
+  ASSERT_TRUE(!!ewh);
   StubForTest(ewh);
   EXPECT_TRUE(is_idle(ewh));
   EXPECT_FALSE(is_ui_shown(ewh));
-
-  ewh.HandleExitKey(true);
+  EXPECT_TRUE(ProcessWithContext(press));
   EXPECT_TRUE(is_ui_shown(ewh));
   SimulateTimer1Expired(ewh); // simulate double press timer expired
-  ewh.HandleExitKey(false); // release before long hold limit
+  EXPECT_FALSE(ProcessWithContext(release));
   SimulateTimer2Expired(ewh); // simulate long hold timer expired
   EXPECT_FALSE(is_ui_shown(ewh));
   EXPECT_TRUE(is_idle(ewh));
+  Reset(ewh);
 }
 
-// Release of exit key before double press limit => cancel.
+// Second Press after double press time limit => cancel
 TEST_F(AcceleratorControllerTest, ExitWarningHandlerTestQuickRelease) {
-  ExitWarningHandler ewh;
+  ui::Accelerator press(ui::VKEY_Q, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN);
+  ui::Accelerator release(press);
+  release.set_type(ui::ET_KEY_RELEASED);
+  ExitWarningHandler* ewh = GetController()->GetExitWarningHandlerForTest();
+  ASSERT_TRUE(!!ewh);
   StubForTest(ewh);
   EXPECT_TRUE(is_idle(ewh));
   EXPECT_FALSE(is_ui_shown(ewh));
-
-  ewh.HandleExitKey(true);
+  EXPECT_TRUE(ProcessWithContext(press));
+  EXPECT_FALSE(ProcessWithContext(release));
   EXPECT_TRUE(is_ui_shown(ewh));
-  ewh.HandleExitKey(false); // release before double press limit
   SimulateTimer1Expired(ewh); // simulate double press timer expired
+  EXPECT_TRUE(ProcessWithContext(press));
   SimulateTimer2Expired(ewh); // simulate long hold timer expired
   EXPECT_FALSE(is_ui_shown(ewh));
   EXPECT_TRUE(is_idle(ewh));
+  Reset(ewh);
 }
+#endif  // !defined(OS_WIN)
 
 TEST_F(AcceleratorControllerTest, Register) {
   const ui::Accelerator accelerator_a(ui::VKEY_A, ui::EF_NONE);
@@ -948,17 +967,18 @@ TEST_F(AcceleratorControllerTest, GlobalAccelerators) {
   // Exit
   ExitWarningHandler* ewh = GetController()->GetExitWarningHandlerForTest();
   ASSERT_TRUE(!!ewh);
-  StubForTest(*ewh);
-  EXPECT_TRUE(is_idle(*ewh));
-  EXPECT_FALSE(is_ui_shown(*ewh));
+  StubForTest(ewh);
+  EXPECT_TRUE(is_idle(ewh));
+  EXPECT_FALSE(is_ui_shown(ewh));
   EXPECT_TRUE(ProcessWithContext(
       ui::Accelerator(ui::VKEY_Q, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN)));
-  EXPECT_FALSE(is_idle(*ewh));
-  EXPECT_TRUE(is_ui_shown(*ewh));
-  SimulateTimer1Expired(*ewh);
-  SimulateTimer2Expired(*ewh);
-  EXPECT_FALSE(is_ui_shown(*ewh));
-  EXPECT_TRUE(is_exiting(*ewh));
+  EXPECT_FALSE(is_idle(ewh));
+  EXPECT_TRUE(is_ui_shown(ewh));
+  SimulateTimer1Expired(ewh);
+  SimulateTimer2Expired(ewh);
+  EXPECT_FALSE(is_ui_shown(ewh));
+  EXPECT_TRUE(is_exiting(ewh));
+  Reset(ewh);
 #endif
 
   // New tab
diff --git a/ash/accelerators/accelerator_table.cc b/ash/accelerators/accelerator_table.cc
index ec32f2c..e60408e 100644
--- a/ash/accelerators/accelerator_table.cc
+++ b/ash/accelerators/accelerator_table.cc
@@ -73,8 +73,7 @@ const AcceleratorData kAcceleratorData[] = {
 #endif  // defined(OS_CHROMEOS)
   { true, ui::VKEY_I, ui::EF_SHIFT_DOWN | ui::EF_ALT_DOWN, OPEN_FEEDBACK_PAGE },
 #if !defined(OS_WIN)
-  { true, ui::VKEY_Q, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN, EXIT_PRESSED },
-  { false, ui::VKEY_Q, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN, EXIT_RELEASED },
+  { true, ui::VKEY_Q, ui::EF_SHIFT_DOWN | ui::EF_CONTROL_DOWN, EXIT },
 #endif
   { true, ui::VKEY_I, ui::EF_CONTROL_DOWN | ui::EF_ALT_DOWN,
     TOUCH_HUD_MODE_CHANGE },
@@ -280,8 +279,7 @@ const size_t kActionsAllowedAtLoginOrLockScreenLength =
     arraysize(kActionsAllowedAtLoginOrLockScreen);
 
 const AcceleratorAction kActionsAllowedAtLockScreen[] = {
-  EXIT_PRESSED,
-  EXIT_RELEASED
+  EXIT,
 };
 
 const size_t kActionsAllowedAtLockScreenLength =
@@ -291,8 +289,7 @@ const AcceleratorAction kActionsAllowedAtModalWindow[] = {
   BRIGHTNESS_DOWN,
   BRIGHTNESS_UP,
   DISABLE_CAPS_LOCK,
-  EXIT_PRESSED,
-  EXIT_RELEASED,
+  EXIT,
   KEYBOARD_BRIGHTNESS_DOWN,
   KEYBOARD_BRIGHTNESS_UP,
   MAGNIFY_SCREEN_ZOOM_IN,
@@ -335,6 +332,7 @@ const AcceleratorAction kNonrepeatableActions[] = {
   CYCLE_BACKWARD_MRU,
   CYCLE_FORWARD_LINEAR,
   CYCLE_FORWARD_MRU,
+  EXIT,
   PRINT_UI_HIERARCHIES,  // Don't fill the logs if the key is held down.
   ROTATE_SCREEN,
   ROTATE_WINDOW,
@@ -357,8 +355,7 @@ const AcceleratorAction kActionsAllowedInAppMode[] = {
   CYCLE_FORWARD_LINEAR,
   CYCLE_FORWARD_MRU,
   DISABLE_CAPS_LOCK,
-  EXIT_PRESSED,
-  EXIT_RELEASED,
+  EXIT,
   KEYBOARD_BRIGHTNESS_DOWN,
   KEYBOARD_BRIGHTNESS_UP,
   MAGNIFY_SCREEN_ZOOM_IN,  // Control+F7
diff --git a/ash/accelerators/accelerator_table.h b/ash/accelerators/accelerator_table.h
index ee635f4..7e5e456 100644
--- a/ash/accelerators/accelerator_table.h
+++ b/ash/accelerators/accelerator_table.h
@@ -28,8 +28,7 @@ enum AcceleratorAction {
   DEBUG_TOGGLE_SHOW_FPS_COUNTER,
   DEBUG_TOGGLE_SHOW_PAINT_RECTS,
   DISABLE_CAPS_LOCK,
-  EXIT_PRESSED,
-  EXIT_RELEASED,
+  EXIT,
   FOCUS_LAUNCHER,
   FOCUS_NEXT_PANE,
   FOCUS_PREVIOUS_PANE,
diff --git a/ash/accelerators/exit_warning_handler.cc b/ash/accelerators/exit_warning_handler.cc
index a285560..aa26683 100644
--- a/ash/accelerators/exit_warning_handler.cc
+++ b/ash/accelerators/exit_warning_handler.cc
@@ -4,6 +4,7 @@
 
 #include "ash/accelerators/exit_warning_handler.h"
 
+#include "ash/accelerators/accelerator_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "ash/shell_window_ids.h"
@@ -26,7 +27,7 @@ namespace ash {
 namespace {
 
 const int64 kDoublePressTimeOutMilliseconds = 300;
-const int64 kHoldTimeOutMilliseconds = 1700;
+const int64 kHoldTimeOutMilliseconds = 1000;
 const SkColor kForegroundColor = 0xFFFFFFFF;
 const SkColor kBackgroundColor = 0xE0808080;
 const int kHorizontalMarginAroundText = 100;
@@ -73,10 +74,11 @@ class ExitWarningWidgetDelegateView : public views::WidgetDelegateView {
 
 } // namespace
 
-ExitWarningHandler::ExitWarningHandler()
-  : state_(IDLE),
-    widget_(NULL),
-    stub_timers_for_test_(false) {
+ExitWarningHandler::ExitWarningHandler(AcceleratorControllerContext* context)
+    : context_(context),
+      state_(IDLE),
+      widget_(NULL),
+      stub_timers_for_test_(false) {
 }
 
 ExitWarningHandler::~ExitWarningHandler() {
@@ -84,30 +86,24 @@ ExitWarningHandler::~ExitWarningHandler() {
   Hide();
 }
 
-void ExitWarningHandler::HandleExitKey(bool press) {
+void ExitWarningHandler::HandleAccelerator() {
+  if (!context_)
+    return;
   switch (state_) {
     case IDLE:
-      if (press) {
-        state_ = WAIT_FOR_QUICK_RELEASE;
-        Show();
-        StartTimers();
-      }
-      break;
-    case WAIT_FOR_QUICK_RELEASE:
-      if (!press)
-        state_ = WAIT_FOR_DOUBLE_PRESS;
+      state_ = WAIT_FOR_DOUBLE_PRESS;
+      accelerator_ = context_->current_accelerator();
+      Show();
+      StartTimers();
       break;
     case WAIT_FOR_DOUBLE_PRESS:
-      if (press) {
-        state_ = EXITING;
-        CancelTimers();
-        Hide();
-        Shell::GetInstance()->delegate()->Exit();
-      }
+      state_ = EXITING;
+      CancelTimers();
+      Hide();
+      Shell::GetInstance()->delegate()->Exit();
       break;
     case WAIT_FOR_LONG_HOLD:
-      if (!press)
-        state_ = CANCELED;
+      state_ = CANCELED;
       break;
     case CANCELED:
     case EXITING:
@@ -119,21 +115,25 @@ void ExitWarningHandler::HandleExitKey(bool press) {
 }
 
 void ExitWarningHandler::Timer1Action() {
-  if (state_ == WAIT_FOR_QUICK_RELEASE)
+  if (state_ == WAIT_FOR_DOUBLE_PRESS)
     state_ = WAIT_FOR_LONG_HOLD;
-  else if (state_ == WAIT_FOR_DOUBLE_PRESS)
-    state_ = CANCELED;
 }
 
 void ExitWarningHandler::Timer2Action() {
+  Hide();
   if (state_ == CANCELED) {
     state_ = IDLE;
-    Hide();
-  }
-  else if (state_ == WAIT_FOR_LONG_HOLD) {
-    state_ = EXITING;
-    Hide();
-    Shell::GetInstance()->delegate()->Exit();
+  } else if (state_ == WAIT_FOR_LONG_HOLD) {
+    if (accelerator_ == context_->current_accelerator()) {
+      // We detect if the user has released any one of the keys that
+      // make up the shortcut by comparing "our" accelerator to the one
+      // from the current context and do not exit in that case.
+      state_ = EXITING;
+      Shell::GetInstance()->delegate()->Exit();
+    }
+    else {
+      state_ = IDLE;
+    }
   }
 }
 
diff --git a/ash/accelerators/exit_warning_handler.h b/ash/accelerators/exit_warning_handler.h
index 5b3d718e..3cb96f2 100644
--- a/ash/accelerators/exit_warning_handler.h
+++ b/ash/accelerators/exit_warning_handler.h
@@ -7,6 +7,7 @@
 
 #include "ash/ash_export.h"
 #include "base/timer.h"
+#include "ui/base/accelerators/accelerator.h"
 
 namespace views {
 class Widget;
@@ -19,12 +20,16 @@ namespace ash {
 // a period of time. During that time we show a popup informing the
 // user of this. We exit only if the user holds the shortcut longer
 // than this time limit.
-// An expert user may quickly release and then press again (double press)
-// for immediate exit. The press, release and press must happen within
-// the double press time limit.
-// If the user releases (without double press) before the required hold
-// time, we will cancel the exit, but show the ui until the hold time limit
-// has expired to avoid a short popup flash.
+// An expert user may double press the shortcut for immediate exit.
+// The double press must happen within the double press time limit.
+// Unless the user performs a double press, we show the ui until the
+// hold time limit has expired to avoid a short popup flash.
+//
+// Notes:
+//
+// The corresponding accelerator must be non-repeatable (see
+// kNonrepeatableActions in accelerator_table.cc). Otherwise the "Double Press
+// Exit" will be activated just by holding it down, i.e. probably every time.
 //
 // State Transition Diagrams:
 //
@@ -33,58 +38,56 @@ namespace ash {
 //
 //  IDLE
 //   | Press
-//  WAIT_FOR_QUICK_RELEASE action: show ui & start timers
-//   | Release (DT < T1)
-//  WAIT_FOR_DOUBLE_PRESS
+//  WAIT_FOR_DOUBLE_PRESS action: show ui & start timers
 //   | Press (DT < T1)
 //  EXITING action: hide ui, stop timers, exit
 //
 //  IDLE
 //   | Press
-//  WAIT_FOR_QUICK_RELEASE action: show ui & start timers
+//  WAIT_FOR_DOUBLE_PRESS action: show ui & start timers
 //   | T1 timer expires
 //  WAIT_FOR_LONG_HOLD
-//   | T2 Timer exipres
+//   | T2 Timer exipres and
+//   | accelerator was held (matches current accelerator from context)
 //  EXITING action: hide ui, exit
 //
 //  IDLE
 //   | Press
-//  WAIT_FOR_QUICK_RELEASE action: show ui & start timers
-//   | T1 timer expiers
+//  WAIT_FOR_DOUBLE_PRESS action: show ui & start timers
+//   | T1 timer expires
 //  WAIT_FOR_LONG_HOLD
-//   | Release
-//  CANCELED
-//   | T2 timer expires
+//   | T2 Timer exipres and
+//   | accelerator was not held
 //  IDLE action: hide ui
 //
 //  IDLE
 //   | Press
-//  WAIT_FOR_QUICK_RELEASE action: show ui & start timers
-//   | Release (DT < T1)
-//  WAIT_FOR_DOUBLE_PRESS
+//  WAIT_FOR_DOUBLE_PRESS action: show ui & start timers
 //   | T1 timer expires
+//  WAIT_FOR_LONG_HOLD
+//   | Press
 //  CANCELED
 //   | T2 timer expires
 //  IDLE action: hide ui
 //
 
+class AcceleratorControllerContext;
 class AcceleratorControllerTest;
 
 class ASH_EXPORT ExitWarningHandler {
  public:
-  ExitWarningHandler();
+  explicit ExitWarningHandler(AcceleratorControllerContext* context);
 
   ~ExitWarningHandler();
 
-  // Handles shortcut key press and release (Ctrl-Shift-Q).
-  void HandleExitKey(bool press);
+  // Handles accelerator for exit (Ctrl-Shift-Q).
+  void HandleAccelerator();
 
  private:
   friend class AcceleratorControllerTest;
 
   enum State {
     IDLE,
-    WAIT_FOR_QUICK_RELEASE,
     WAIT_FOR_DOUBLE_PRESS,
     WAIT_FOR_LONG_HOLD,
     CANCELED,
@@ -107,6 +110,11 @@ class ASH_EXPORT ExitWarningHandler {
   void Show();
   void Hide();
 
+  // AcceleratorControllerContext is used when a timer expires to test
+  // whether the user has held the accelerator key combination or has
+  // released (at least) one of the keys.
+  AcceleratorControllerContext* context_;
+  ui::Accelerator accelerator_;
   State state_;
   views::Widget* widget_; // owned by |this|.
   base::OneShotTimer<ExitWarningHandler> timer1_; // short; double press