Intorduce PowerButtonObserver API

athena/system/power_button_controller.cc

Index: athena/system/power_button_controller.cc
diff --git a/athena/system/power_button_controller.cc b/athena/system/power_button_controller.cc
index e1105b90e9ad458f4816dfc5d525aa5e4247813d..3926b6da9728bd10545a49242b673506315b4237 100644
--- a/athena/system/power_button_controller.cc
+++ b/athena/system/power_button_controller.cc
@@ -7,6 +7,7 @@
 #include "athena/screen/public/screen_manager.h"
 #include "athena/strings/grit/athena_strings.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
+#include "chromeos/dbus/power_manager_client.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/font_list.h"
 #include "ui/views/background.h"
@@ -18,27 +19,20 @@
 namespace athena {
 namespace {
 
-// The amount of time that the power button must be held to show the shutdown
-// warning dialog.
-const int kShowShutdownWarningTimeoutMs = 1000;
-
 // The amount of time that the power button must be held to shut down the
-// device.
-const int kShutdownTimeoutMs = 5000;
+// device after shutdown dialog is shown.
+const int kShutdownTimeoutMs = 4000;
 
 }  // namespace
 
 PowerButtonController::PowerButtonController(aura::Window* dialog_container)
     : warning_message_container_(dialog_container),
-      brightness_is_zero_(false),
       state_(STATE_OTHER) {
-  chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->AddObserver(
-      this);
+  InputManager::Get()->AddPowerButtonObserver(this);
 }
 
 PowerButtonController::~PowerButtonController() {
-  chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->RemoveObserver(
-      this);
+  InputManager::Get()->RemovePowerButtonObserver(this);
 }
 
 void PowerButtonController::ShowShutdownWarningDialog() {
@@ -69,10 +63,8 @@ void PowerButtonController::ShowShutdownWarningDialog() {
   shutdown_warning_message_->SetContentsView(container);
   shutdown_warning_message_->CenterWindow(container->GetPreferredSize());
   shutdown_warning_message_->Show();
-
   timer_.Start(FROM_HERE,
-               base::TimeDelta::FromMilliseconds(kShutdownTimeoutMs -
-                                                 kShowShutdownWarningTimeoutMs),
+               base::TimeDelta::FromMilliseconds(kShutdownTimeoutMs),
                this,
                &PowerButtonController::Shutdown);
 }
@@ -84,42 +76,28 @@ void PowerButtonController::Shutdown() {
       ->RequestShutdown();
 }
 
-void PowerButtonController::BrightnessChanged(int level, bool user_initiated) {
-  if (brightness_is_zero_)
-    zero_brightness_end_time_ = base::TimeTicks::Now();
-  brightness_is_zero_ = (level == 0);
-}
-
-void PowerButtonController::PowerButtonEventReceived(
-    bool down,
-    const base::TimeTicks& timestamp) {
+void PowerButtonController::OnPowerButtonStateChanged(
+    PowerButtonObserver::State state) {
   if (state_ == STATE_SHUTDOWN_REQUESTED)
     return;
 
-  // Avoid requesting suspend or shutdown if the power button is pressed while
-  // the screen is off (http://crbug.com/128451).
-  base::TimeDelta time_since_zero_brightness = brightness_is_zero_ ?
-      base::TimeDelta() : (base::TimeTicks::Now() - zero_brightness_end_time_);
-  const int kShortTimeMs = 10;
-  if (time_since_zero_brightness.InMilliseconds() <= kShortTimeMs)
-    return;
-
-  if (down) {
-    state_ = STATE_SUSPEND_ON_RELEASE;
-    timer_.Start(
-        FROM_HERE,
-        base::TimeDelta::FromMilliseconds(kShowShutdownWarningTimeoutMs),
-        this,
-        &PowerButtonController::ShowShutdownWarningDialog);
-  } else {
-    if (state_ == STATE_SUSPEND_ON_RELEASE) {
-      chromeos::DBusThreadManager::Get()
-          ->GetPowerManagerClient()
-          ->RequestSuspend();
-    }
-    state_ = STATE_OTHER;
-    timer_.Stop();
-    shutdown_warning_message_.reset();
+  switch (state) {
+    case PRESSED:
+      state_ = STATE_SUSPEND_ON_RELEASE;
+      break;
+    case LONG_PRESSED:
+      ShowShutdownWarningDialog();
+      break;
+    case RELEASED:
+      if (state_ == STATE_SUSPEND_ON_RELEASE) {
+        chromeos::DBusThreadManager::Get()
+            ->GetPowerManagerClient()
+            ->RequestSuspend();
+      }
+      state_ = STATE_OTHER;
+      timer_.Stop();
+      shutdown_warning_message_.reset();
+      break;
   }
 }