HID-detection screen moved to screenContext.

chrome/browser/chromeos/login/screens/hid_detection_screen.cc

Index: chrome/browser/chromeos/login/screens/hid_detection_screen.cc
diff --git a/chrome/browser/chromeos/login/screens/hid_detection_screen.cc b/chrome/browser/chromeos/login/screens/hid_detection_screen.cc
index 99b6e48098a52fc6fc06853437608cb022e30f90..507c45c002a2d7fc406a50105245eef70dbdb8ad 100644
--- a/chrome/browser/chromeos/login/screens/hid_detection_screen.cc
+++ b/chrome/browser/chromeos/login/screens/hid_detection_screen.cc
@@ -4,48 +4,546 @@
 
 #include "chrome/browser/chromeos/login/screens/hid_detection_screen.h"
 
+#include "base/bind.h"
+#include "base/metrics/histogram.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/chromeos/login/screens/base_screen_delegate.h"
+#include "chrome/browser/chromeos/login/screens/hid_detection_view.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
+#include "chrome/grit/generated_resources.h"
+#include "device/bluetooth/bluetooth_adapter_factory.h"
+#include "ui/base/l10n/l10n_util.h"
+
+namespace {
+
+// Possible ui-states for device-blocks.
+const char kSearchingState[] = "searching";
+const char kUSBConnectedState[] = "connected";
+const char kBTPairedState[] = "paired";
+const char kBTPairingState[] = "pairing";
+
+// Standard length of pincode for pairing BT keyboards.
+const int kPincodeLength = 6;
+
+bool DeviceIsPointing(device::BluetoothDevice::DeviceType device_type) {
+  return device_type == device::BluetoothDevice::DEVICE_MOUSE ||
+         device_type == device::BluetoothDevice::DEVICE_KEYBOARD_MOUSE_COMBO ||
+         device_type == device::BluetoothDevice::DEVICE_TABLET;
+}
+
+bool DeviceIsPointing(const device::InputServiceLinux::InputDeviceInfo& info) {
+  return info.is_mouse || info.is_touchpad || info.is_touchscreen ||
+         info.is_tablet;
+}
+
+bool DeviceIsKeyboard(device::BluetoothDevice::DeviceType device_type) {
+  return device_type == device::BluetoothDevice::DEVICE_KEYBOARD ||
+         device_type == device::BluetoothDevice::DEVICE_KEYBOARD_MOUSE_COMBO;
+}
+
+}  // namespace
 
 namespace chromeos {
 
 HIDDetectionScreen::HIDDetectionScreen(BaseScreenDelegate* base_screen_delegate,
-                                       HIDDetectionScreenActor* actor)
-    : BaseScreen(base_screen_delegate), actor_(actor) {
-  DCHECK(actor_);
-  if (actor_)
-    actor_->SetDelegate(this);
+                                       HIDDetectionView* view)
+    : HIDDetectionModel(base_screen_delegate),
+      view_(view),
+      mouse_is_pairing_(false),
+      pointing_device_connect_type_(InputDeviceInfo::TYPE_UNKNOWN),
+      keyboard_is_pairing_(false),
+      keyboard_device_connect_type_(InputDeviceInfo::TYPE_UNKNOWN),
+      switch_on_adapter_when_ready_(false),
+      showing_(false),
+      weak_ptr_factory_(this) {
+  DCHECK(view_);
+  if (view_)
+    view_->Bind(*this);
+
 }
 
 HIDDetectionScreen::~HIDDetectionScreen() {
-  if (actor_)
-    actor_->SetDelegate(NULL);
+  adapter_initially_powered_.reset();
+  input_service_proxy_.RemoveObserver(this);
+  if (view_)
+    view_->Unbind();
+  if (discovery_session_.get())
+    discovery_session_->Stop(base::Bind(&base::DoNothing),
+                             base::Bind(&base::DoNothing));
+  if (adapter_.get())
+    adapter_->RemoveObserver(this);
 }
 
 void HIDDetectionScreen::PrepareToShow() {
+  if (view_)
+    view_->PrepareToShow();
 }
 
 void HIDDetectionScreen::Show() {
-  if (actor_)
-    actor_->Show();
+  showing_ = true;
+  GetContextEditor().SetBoolean(kContextKeyNumKeysEnteredExpected, false);

[Denis Kuznetsov (DE-MUC), 2015/02/11 16:09:24]

Here update will be sent in the end of the method, so on JS side you will
receive update after Pointing/Keyboard device notifications. If you need this
update before, enclose it to braces:
{ 
 GetEditor().SetNNN();
}

+  SendPointingDeviceNotification();
+  SendKeyboardDeviceNotification();
+
+  input_service_proxy_.AddObserver(this);
+  UpdateDevices();
+
+  if (view_)
+    view_->Show();
 }
 
 void HIDDetectionScreen::Hide() {
-  if (actor_)
-    actor_->Hide();
+  showing_ = false;
+  input_service_proxy_.RemoveObserver(this);
+  if (discovery_session_.get())
+    discovery_session_->Stop(base::Bind(&base::DoNothing),
+                             base::Bind(&base::DoNothing));
+  if (view_)
+    view_->Hide();
 }
 
-std::string HIDDetectionScreen::GetName() const {
-  return WizardController::kHIDDetectionScreenName;
+void HIDDetectionScreen::Initialize(::login::ScreenContext* context) {
+  HIDDetectionModel::Initialize(context);
+
+  device::BluetoothAdapterFactory::GetAdapter(
+      base::Bind(&HIDDetectionScreen::InitializeAdapter,
+                 weak_ptr_factory_.GetWeakPtr()));
 }
 
-void HIDDetectionScreen::OnExit() {
+void HIDDetectionScreen::OnContinueButtonClicked() {
+
+  ContinueScenarioType scenario_type;
+  if (!pointing_device_id_.empty() && !keyboard_device_id_.empty())
+    scenario_type = All_DEVICES_DETECTED;
+  else if (pointing_device_id_.empty())
+    scenario_type = KEYBOARD_DEVICE_ONLY_DETECTED;
+  else
+    scenario_type = POINTING_DEVICE_ONLY_DETECTED;
+
+  UMA_HISTOGRAM_ENUMERATION(
+      "HIDDetection.OOBEDevicesDetectedOnContinuePressed",
+      scenario_type,
+      CONTINUE_SCENARIO_TYPE_SIZE);
+
+  // Switch off BT adapter if it was off before the screen and no BT device
+  // connected.
+  bool adapter_is_powered =
+      adapter_.get() && adapter_->IsPresent() && adapter_->IsPowered();
+  bool use_bluetooth =
+      pointing_device_connect_type_ == InputDeviceInfo::TYPE_BLUETOOTH ||
+      keyboard_device_connect_type_ == InputDeviceInfo::TYPE_BLUETOOTH;
+  bool need_switching_off = adapter_initially_powered_ &&
+                            !(*adapter_initially_powered_);
+  if (adapter_is_powered && !use_bluetooth && need_switching_off) {
+    VLOG(1) << "Switching off BT adapter after HID OOBE screen as unused.";
+    adapter_->SetPowered(
+        false,
+        base::Bind(&base::DoNothing),
+        base::Bind(&HIDDetectionScreen::SetPoweredOffError,
+                   weak_ptr_factory_.GetWeakPtr()));
+  }
+
   Finish(BaseScreenDelegate::HID_DETECTION_COMPLETED);
 }
 
-void HIDDetectionScreen::OnActorDestroyed(HIDDetectionScreenActor* actor) {
-  if (actor_ == actor)
-    actor_ = NULL;
+void HIDDetectionScreen::CheckIsScreenRequired(
+      const base::Callback<void(bool)>& on_check_done) {
+  input_service_proxy_.GetDevices(
+      base::Bind(&HIDDetectionScreen::OnGetInputDevicesListForCheck,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 on_check_done));
+}
+
+void HIDDetectionScreen::OnViewDestroyed(HIDDetectionView* view) {
+  if (view_ == view)
+    view_ = NULL;
+}
+
+void HIDDetectionScreen::RequestPinCode(device::BluetoothDevice* device) {
+  VLOG(1) << "RequestPinCode id = " << device->GetDeviceID()
+          << " name = " << device->GetName();
+  device->CancelPairing();
+}
+
+void HIDDetectionScreen::RequestPasskey(device::BluetoothDevice* device) {
+  VLOG(1) << "RequestPassKey id = " << device->GetDeviceID()
+          << " name = " << device->GetName();
+  device->CancelPairing();
+}
+
+void HIDDetectionScreen::DisplayPinCode(device::BluetoothDevice* device,
+                                        const std::string& pincode) {
+  VLOG(1) << "DisplayPinCode id = " << device->GetDeviceID()
+          << " name = " << device->GetName();
+  GetContextEditor().SetString(kContextKeyPinCode, pincode);

[Denis Kuznetsov (DE-MUC), 2015/02/11 16:09:24]

Same as above, make sure that expectations on JS side are the same.

+  SetKeyboardDeviceName_(base::UTF16ToUTF8(device->GetName()));
+  SendKeyboardDeviceNotification();
+}
+
+void HIDDetectionScreen::DisplayPasskey(
+    device::BluetoothDevice* device, uint32 passkey) {
+  VLOG(1) << "DisplayPassKey id = " << device->GetDeviceID()
+          << " name = " << device->GetName();
+  std::string pincode = base::UintToString(passkey);
+  pincode = std::string(kPincodeLength - pincode.length(), '0').append(pincode);
+  // No differences in UI for passkey and pincode authentication calls.
+  DisplayPinCode(device, pincode);
+}
+
+void HIDDetectionScreen::KeysEntered(
+    device::BluetoothDevice* device, uint32 entered) {
+  VLOG(1) << "Number of keys entered " << entered;
+  GetContextEditor()
+      .SetBoolean(kContextKeyNumKeysEnteredExpected, true)
+      .SetInteger(kContextKeyNumKeysEnteredPinCode, entered);

[Denis Kuznetsov (DE-MUC), 2015/02/11 16:09:24]

Same as above.

+  SendKeyboardDeviceNotification();
+}
+
+void HIDDetectionScreen::ConfirmPasskey(
+    device::BluetoothDevice* device, uint32 passkey) {
+  VLOG(1) << "Confirm Passkey";
+  device->CancelPairing();
+}
+
+void HIDDetectionScreen::AuthorizePairing(device::BluetoothDevice* device) {
+  // There is never any circumstance where this will be called, since the
+  // HID detection screen will only be used for outgoing pairing
+  // requests, but play it safe.
+  VLOG(1) << "Authorize pairing";
+  device->ConfirmPairing();
+}
+
+void HIDDetectionScreen::AdapterPresentChanged(
+    device::BluetoothAdapter* adapter, bool present) {
+  if (present && switch_on_adapter_when_ready_) {
+    VLOG(1) << "Switching on BT adapter on HID OOBE screen.";
+    adapter_initially_powered_.reset(new bool(adapter_->IsPowered()));
+    adapter_->SetPowered(
+        true,
+        base::Bind(&HIDDetectionScreen::StartBTDiscoverySession,
+                   weak_ptr_factory_.GetWeakPtr()),
+        base::Bind(&HIDDetectionScreen::SetPoweredError,
+                   weak_ptr_factory_.GetWeakPtr()));
+  }
+}
+
+void HIDDetectionScreen::TryPairingAsPointingDevice(
+    device::BluetoothDevice* device) {
+  if (pointing_device_id_.empty() &&
+      DeviceIsPointing(device->GetDeviceType()) &&
+      device->IsPairable() &&
+      !(device->IsConnected() && device->IsPaired()) &&
+      !mouse_is_pairing_) {
+    ConnectBTDevice(device);
+  }
+}
+
+void HIDDetectionScreen::TryPairingAsKeyboardDevice(
+    device::BluetoothDevice* device) {
+  if (keyboard_device_id_.empty() &&
+      DeviceIsKeyboard(device->GetDeviceType()) &&
+      device->IsPairable() &&
+      !(device->IsConnected() && device->IsPaired()) &&
+      !keyboard_is_pairing_) {
+    ConnectBTDevice(device);
+  }
+}
+
+void HIDDetectionScreen::ConnectBTDevice(device::BluetoothDevice* device) {
+  bool device_busy = (device->IsConnected() && device->IsPaired()) ||
+                      device->IsConnecting();
+  if (!device->IsPairable() || device_busy)
+    return;
+  device::BluetoothDevice::DeviceType device_type = device->GetDeviceType();
+
+  if (device_type == device::BluetoothDevice::DEVICE_MOUSE ||
+      device_type == device::BluetoothDevice::DEVICE_TABLET) {
+    if (mouse_is_pairing_)
+      return;
+    mouse_is_pairing_ = true;
+  } else if (device_type == device::BluetoothDevice::DEVICE_KEYBOARD) {
+    if (keyboard_is_pairing_)
+      return;
+    keyboard_is_pairing_ = true;
+  } else if (device_type ==
+      device::BluetoothDevice::DEVICE_KEYBOARD_MOUSE_COMBO) {
+    if (mouse_is_pairing_ && keyboard_is_pairing_)
+      return;
+    mouse_is_pairing_ = true;
+    keyboard_is_pairing_ = true;
+  }
+  device->Connect(this,
+            base::Bind(&HIDDetectionScreen::BTConnected,
+                       weak_ptr_factory_.GetWeakPtr(), device_type),
+            base::Bind(&HIDDetectionScreen::BTConnectError,
+                       weak_ptr_factory_.GetWeakPtr(),
+                       device->GetAddress(), device_type));
+}
+
+void HIDDetectionScreen::BTConnected(
+    device::BluetoothDevice::DeviceType device_type) {
+  if (DeviceIsPointing(device_type))
+    mouse_is_pairing_ = false;
+  if (DeviceIsKeyboard(device_type)) {
+    keyboard_is_pairing_ = false;
+    GetContextEditor()

[Denis Kuznetsov (DE-MUC), 2015/02/11 16:09:24]

same here

+        .SetBoolean(kContextKeyNumKeysEnteredExpected, false)
+        .SetString(kContextKeyPinCode, "");
+    SendKeyboardDeviceNotification();
+  }
+}
+
+void HIDDetectionScreen::BTConnectError(
+    const std::string& address,
+    device::BluetoothDevice::DeviceType device_type,
+    device::BluetoothDevice::ConnectErrorCode error_code) {
+  LOG(WARNING) << "BTConnectError while connecting " << address
+               << " error code = " << error_code;
+  if (DeviceIsPointing(device_type))
+    mouse_is_pairing_ = false;
+  if (DeviceIsKeyboard(device_type)) {
+    keyboard_is_pairing_ = false;
+    GetContextEditor()
+        .SetInteger(kContextKeyNumKeysEnteredExpected, false)
+        .SetString(kContextKeyPinCode, "");

[Denis Kuznetsov (DE-MUC), 2015/02/11 16:09:24]

same here

+    SendKeyboardDeviceNotification();
+  }
+
+  if (pointing_device_id_.empty() || keyboard_device_id_.empty())
+    UpdateDevices();
+}
+
+void HIDDetectionScreen::SendPointingDeviceNotification() {
+  std::string state;
+  if (pointing_device_id_.empty())
+    state = kSearchingState;
+  else if (pointing_device_connect_type_ == InputDeviceInfo::TYPE_BLUETOOTH)
+    state = kBTPairedState;
+  else
+    state = kUSBConnectedState;
+  GetContextEditor().SetString(kContextKeyMouseState, state)
+                    .SetBoolean(
+      kContextKeyContinueButtonEnabled,
+      !(pointing_device_id_.empty() && keyboard_device_id_.empty()));
+}
+
+void HIDDetectionScreen::SendKeyboardDeviceNotification() {
+  ContextEditor editor = GetContextEditor();
+  editor.SetString(kContextKeyKeyboardLabel, "");
+  if (keyboard_device_id_.empty()) {
+    if (keyboard_is_pairing_) {
+      editor.SetString(kContextKeyKeyboardState, kBTPairingState)
+            .SetString(
+          kContextKeyKeyboardLabel,
+          l10n_util::GetStringFUTF8(
+              IDS_HID_DETECTION_BLUETOOTH_REMOTE_PIN_CODE_REQUEST,
+              base::UTF8ToUTF16(keyboard_device_name_)));
+    } else {
+      editor.SetString(kContextKeyKeyboardState, kSearchingState);
+    }
+  } else {
+    if (keyboard_device_connect_type_ == InputDeviceInfo::TYPE_BLUETOOTH) {
+      editor.SetString(kContextKeyKeyboardState, kBTPairedState)
+            .SetString(
+                kContextKeyKeyboardLabel,
+                l10n_util::GetStringFUTF16(
+                    IDS_HID_DETECTION_PAIRED_BLUETOOTH_KEYBOARD,
+                    base::UTF8ToUTF16(keyboard_device_name_)));
+    } else {
+      editor.SetString(kContextKeyKeyboardState, kUSBConnectedState);
+    }
+  }
+  editor.SetString(kContextKeyKeyboardDeviceName, keyboard_device_name_)
+        .SetBoolean(
+            kContextKeyContinueButtonEnabled,
+            !(pointing_device_id_.empty() && keyboard_device_id_.empty()));
+}
+
+void HIDDetectionScreen::SetKeyboardDeviceName_(std::string name) {
+  if (!(keyboard_device_id_.empty()) && name.empty())
+    name = l10n_util::GetStringUTF8(IDS_HID_DETECTION_DEFAULT_KEYBOARD_NAME);
+  keyboard_device_name_ = name;
+}
+
+void HIDDetectionScreen::DeviceAdded(
+    device::BluetoothAdapter* adapter, device::BluetoothDevice* device) {
+  VLOG(1) << "BT input device added id = " << device->GetDeviceID() <<
+      " name = " << device->GetName();
+  TryPairingAsPointingDevice(device);
+  TryPairingAsKeyboardDevice(device);
+}
+
+void HIDDetectionScreen::DeviceChanged(
+    device::BluetoothAdapter* adapter, device::BluetoothDevice* device) {
+  VLOG(1) << "BT device changed id = " << device->GetDeviceID() << " name = " <<
+      device->GetName();
+  TryPairingAsPointingDevice(device);
+  TryPairingAsKeyboardDevice(device);
+}
+
+void HIDDetectionScreen::DeviceRemoved(
+    device::BluetoothAdapter* adapter, device::BluetoothDevice* device) {
+  VLOG(1) << "BT device removed id = " << device->GetDeviceID() << " name = " <<
+      device->GetName();
+}
+
+void HIDDetectionScreen::OnInputDeviceAdded(
+    const InputDeviceInfo& info) {
+  VLOG(1) << "Input device added id = " << info.id << " name = " << info.name;
+  // TODO(merkulova): deal with all available device types, e.g. joystick.
+  if (!keyboard_device_id_.empty() && !pointing_device_id_.empty())
+    return;
+
+  if (pointing_device_id_.empty() && DeviceIsPointing(info)) {
+    pointing_device_id_ = info.id;
+    GetContextEditor().SetString(kContextKeyMouseDeviceName, info.name);

[Denis Kuznetsov (DE-MUC), 2015/02/11 16:09:24]

same here

+    pointing_device_connect_type_ = info.type;
+    SendPointingDeviceNotification();
+  }
+  if (keyboard_device_id_.empty() && info.is_keyboard) {
+    keyboard_device_id_ = info.id;
+    keyboard_device_connect_type_ = info.type;
+    SetKeyboardDeviceName_(info.name);
+    SendKeyboardDeviceNotification();
+  }
+}
+
+void HIDDetectionScreen::OnInputDeviceRemoved(const std::string& id) {
+  if (id == keyboard_device_id_) {
+    keyboard_device_id_.clear();
+    keyboard_device_connect_type_ = InputDeviceInfo::TYPE_UNKNOWN;
+    SendKeyboardDeviceNotification();
+    UpdateDevices();
+  }
+  if (id == pointing_device_id_) {
+    pointing_device_id_.clear();
+    pointing_device_connect_type_ = InputDeviceInfo::TYPE_UNKNOWN;
+    SendPointingDeviceNotification();
+    UpdateDevices();
+  }
 }
 
+void HIDDetectionScreen::InitializeAdapter(
+    scoped_refptr<device::BluetoothAdapter> adapter) {
+  adapter_ = adapter;
+  CHECK(adapter_.get());
+
+  adapter_->AddObserver(this);
+  UpdateDevices();
+}
+
+void HIDDetectionScreen::StartBTDiscoverySession() {
+  adapter_->StartDiscoverySession(
+      base::Bind(&HIDDetectionScreen::OnStartDiscoverySession,
+                 weak_ptr_factory_.GetWeakPtr()),
+      base::Bind(&HIDDetectionScreen::FindDevicesError,
+                 weak_ptr_factory_.GetWeakPtr()));
+}
+
+void HIDDetectionScreen::ProcessConnectedDevicesList(
+    const std::vector<InputDeviceInfo>& devices) {
+  for (std::vector<InputDeviceInfo>::const_iterator it = devices.begin();
+       it != devices.end() &&
+       (pointing_device_id_.empty() || keyboard_device_id_.empty());
+       ++it) {
+    if (pointing_device_id_.empty() && DeviceIsPointing(*it)) {
+      pointing_device_id_ = it->id;
+      GetContextEditor().SetString(kContextKeyMouseDeviceName, it->name);

[Denis Kuznetsov (DE-MUC), 2015/02/11 16:09:24]

same here

+      pointing_device_connect_type_ = it->type;
+      SendPointingDeviceNotification();
+    }
+    if (keyboard_device_id_.empty() && it->is_keyboard) {
+      keyboard_device_id_ = it->id;
+      SetKeyboardDeviceName_(it->name);
+      keyboard_device_connect_type_ = it->type;
+      SendKeyboardDeviceNotification();
+    }
+  }
+}
+
+void HIDDetectionScreen::TryInitiateBTDevicesUpdate() {
+  if ((pointing_device_id_.empty() || keyboard_device_id_.empty()) &&
+      adapter_.get()) {
+    if (!adapter_->IsPresent()) {
+      // Switch on BT adapter later when it's available.
+      switch_on_adapter_when_ready_ = true;
+    } else if (!adapter_->IsPowered()) {
+      VLOG(1) << "Switching on BT adapter on HID OOBE screen.";
+      adapter_initially_powered_.reset(new bool(false));
+      adapter_->SetPowered(
+          true,
+          base::Bind(&HIDDetectionScreen::StartBTDiscoverySession,
+                     weak_ptr_factory_.GetWeakPtr()),
+          base::Bind(&HIDDetectionScreen::SetPoweredError,
+                     weak_ptr_factory_.GetWeakPtr()));
+    } else {
+      UpdateBTDevices();
+    }
+  }
+}
+
+void HIDDetectionScreen::OnGetInputDevicesListForCheck(
+    const base::Callback<void(bool)>& on_check_done,
+    const std::vector<InputDeviceInfo>& devices) {
+  ProcessConnectedDevicesList(devices);
+
+  // Screen is not required if both devices are present.
+  bool all_devices_autodetected = !pointing_device_id_.empty() &&
+                                  !keyboard_device_id_.empty();
+  UMA_HISTOGRAM_BOOLEAN("HIDDetection.OOBEDialogShown",
+                        !all_devices_autodetected);
+
+  on_check_done.Run(!all_devices_autodetected);
+}
+
+void HIDDetectionScreen::OnGetInputDevicesList(
+    const std::vector<InputDeviceInfo>& devices) {
+  ProcessConnectedDevicesList(devices);
+  TryInitiateBTDevicesUpdate();
+}
+
+void HIDDetectionScreen::UpdateDevices() {
+  input_service_proxy_.GetDevices(
+      base::Bind(&HIDDetectionScreen::OnGetInputDevicesList,
+                 weak_ptr_factory_.GetWeakPtr()));
+}
+
+void HIDDetectionScreen::UpdateBTDevices() {
+  if (!adapter_.get() || !adapter_->IsPresent() || !adapter_->IsPowered())
+    return;
+
+  // If no connected devices found as pointing device and keyboard, we try to
+  // connect some type-suitable active bluetooth device.
+  std::vector<device::BluetoothDevice*> bt_devices = adapter_->GetDevices();
+  for (std::vector<device::BluetoothDevice*>::const_iterator it =
+           bt_devices.begin();
+       it != bt_devices.end() &&
+           (keyboard_device_id_.empty() || pointing_device_id_.empty());
+       ++it) {
+    TryPairingAsPointingDevice(*it);
+    TryPairingAsKeyboardDevice(*it);
+  }
+}
+
+void HIDDetectionScreen::OnStartDiscoverySession(
+    scoped_ptr<device::BluetoothDiscoverySession> discovery_session) {
+  VLOG(1) << "BT Discovery session started";
+  discovery_session_ = discovery_session.Pass();
+  UpdateDevices();
+}
+
+void HIDDetectionScreen::SetPoweredError() {
+  LOG(ERROR) << "Failed to power BT adapter";
+}
+
+void HIDDetectionScreen::SetPoweredOffError() {
+  LOG(ERROR) << "Failed to power off BT adapter";
+}
+
+void HIDDetectionScreen::FindDevicesError() {
+  VLOG(1) << "Failed to start Bluetooth discovery.";
+}
+
+
 }  // namespace chromeos