Fix bluetooth pairing regression

Instead of using ArcBluetoothBridge as the pairing delegate and forward
pairing request to the UI dialog, use BluetoothPairingDialog directly,
which will automatically pair and handling incoming requests.

This would also fix the general bluetooth pairing regression which
incorrectly send the pairing request to ArcBluetoothBridge, so default
handling in BluetoothNotificationController is skipped unexpectedly.

Tested two device pairing flow[A] and ble signin flow[B].

A:
1. Get two chromebooks A and B, with B as your DUT.
2. After login on B, start a terminal, type in "bluetoothctl" and then
   "discoverable on".
3. On A, scan for B and then pair with B.
4. Confirm the passcode on A.
5. Confirm the passcode on B.

1. In settings, navigate to manage Android preferences.
2. Click Accounts to add a google account with a ble security key registered
as the second factor authenticator.
3. Follow the steps and observe a UI dialog show up and ask for passcode.
4. Enter the passcode and the pairing is successful (a notification is shown).

B: 
Change-Id: I48ce5d1968f4d532b72af7df5e5b6e7be586d7d8
Reviewed-on: https://chromium-review.googlesource.com/1109377Reviewed-by: Luis Hector Chavez <lhchavez@chromium.org>
Commit-Queue: Xiaoyin Hu <xiaoyinh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569308}

chrome/browser/chromeos/arc/bluetooth/arc_bluetooth_bridge.cc

@@ -482,10 +482,8 @@ ArcBluetoothBridge::ArcBluetoothBridge(content::BrowserContext* context,
 ArcBluetoothBridge::~ArcBluetoothBridge() {
   DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
 
-  if (bluetooth_adapter_) {
-    bluetooth_adapter_->RemovePairingDelegate(this);
+  if (bluetooth_adapter_)
     bluetooth_adapter_->RemoveObserver(this);
-  }
 
   arc_bridge_service_->bluetooth()->RemoveObserver(this);
   arc_bridge_service_->bluetooth()->SetHost(nullptr);
@@ -503,8 +501,6 @@ void ArcBluetoothBridge::OnAdapterInitialized(
 
   if (!bluetooth_adapter_->HasObserver(this))
     bluetooth_adapter_->AddObserver(this);
-  bluetooth_adapter_->AddPairingDelegate(
-      this, device::BluetoothAdapter::PAIRING_DELEGATE_PRIORITY_HIGH);
 }
 
 void ArcBluetoothBridge::OnConnectionReady() {
@@ -553,22 +549,6 @@ void ArcBluetoothBridge::SendDevice(const BluetoothDevice* device,
                                  std::move(adv_data));
 }
 
-device::BluetoothDevice::PairingDelegate* ArcBluetoothBridge::ShowPairingDialog(
-    device::BluetoothDevice* device) {
-  chromeos::BluetoothPairingDialog::ShowDialog(
-      device::BluetoothDevice::CanonicalizeAddress(device->GetAddress()),
-      device->GetNameForDisplay(), device->IsPaired(), device->IsConnected());
-
-  BluetoothDevice::PairingDelegate* delegate =
-      bluetooth_adapter_->DefaultPairingDelegate();
-  if (!delegate || delegate == this) {
-    OnPairedError(mojom::BluetoothAddress::From(device->GetAddress()),
-                  BluetoothDevice::ERROR_FAILED);
-    return nullptr;
-  }
-  return delegate;
-}
-
 void ArcBluetoothBridge::AdapterPoweredChanged(BluetoothAdapter* adapter,
                                                bool powered) {
   AdapterPowerState power_change =
@@ -1236,12 +1216,11 @@ void ArcBluetoothBridge::CreateBond(mojom::BluetoothAddressPtr addr,
     return;
   }
 
-  // Use this object as the pairing delegate to handle pairing requests.
-  // If pairing finished successfully, DevicePairedChanged will notify Android
-  // on paired state change event, so DoNothing is passed as a success callback.
-  device->Pair(this, base::DoNothing(),
-               base::Bind(&ArcBluetoothBridge::OnPairedError,
-                          weak_factory_.GetWeakPtr(), base::Passed(&addr)));
+  // BluetoothPairingDialog will automatically pair the device and handle all
+  // the incoming pairing requests.
+  chromeos::BluetoothPairingDialog::ShowDialog(
+      device::BluetoothDevice::CanonicalizeAddress(device->GetAddress()),
+      device->GetNameForDisplay(), device->IsPaired(), device->IsConnected());
 }
 
 void ArcBluetoothBridge::RemoveBond(mojom::BluetoothAddressPtr addr) {
@@ -2094,73 +2073,6 @@ void ArcBluetoothBridge::RemoveSdpRecord(uint32_t service_handle,
       base::Bind(&OnRemoveServiceRecordError, repeating_callback));
 }
 
-void ArcBluetoothBridge::RequestPinCode(device::BluetoothDevice* device) {
-  BluetoothDevice::PairingDelegate* delegate = ShowPairingDialog(device);
-
-  // Forward RequestPinCode to extension's pairing delegate to update the UI
-  // dialog properly.
-  if (delegate)
-    delegate->RequestPinCode(device);
-}
-
-void ArcBluetoothBridge::RequestPasskey(device::BluetoothDevice* device) {
-  BluetoothDevice::PairingDelegate* delegate = ShowPairingDialog(device);
-
-  // Forward RequestPasskey to extension's pairing delegate to update the UI
-  // dialog properly.
-  if (delegate)
-    delegate->RequestPasskey(device);
-}
-
-void ArcBluetoothBridge::DisplayPinCode(device::BluetoothDevice* device,
-                                        const std::string& pincode) {
-  BluetoothDevice::PairingDelegate* delegate = ShowPairingDialog(device);
-
-  // Forward DisplayPinCode to extension's pairing delegate to update the UI
-  // dialog properly.
-  if (delegate)
-    delegate->DisplayPinCode(device, pincode);
-}
-
-void ArcBluetoothBridge::DisplayPasskey(device::BluetoothDevice* device,
-                                        uint32_t passkey) {
-  BluetoothDevice::PairingDelegate* delegate = ShowPairingDialog(device);
-
-  // Forward DisplayPasskey to extension's pairing delegate to update the UI
-  // dialog properly.
-  if (delegate)
-    delegate->DisplayPasskey(device, passkey);
-}
-
-void ArcBluetoothBridge::KeysEntered(device::BluetoothDevice* device,
-                                     uint32_t entered) {
-  BluetoothDevice::PairingDelegate* delegate = ShowPairingDialog(device);
-
-  // Forward KeysEntered to extension's pairing delegate to update the UI
-  // dialog properly.
-  if (delegate)
-    delegate->KeysEntered(device, entered);
-}
-
-void ArcBluetoothBridge::ConfirmPasskey(device::BluetoothDevice* device,
-                                        uint32_t passkey) {
-  BluetoothDevice::PairingDelegate* delegate = ShowPairingDialog(device);
-
-  // Forward ConfirmPasskey to extension's pairing delegate to update the UI
-  // dialog properly.
-  if (delegate)
-    delegate->ConfirmPasskey(device, passkey);
-}
-
-void ArcBluetoothBridge::AuthorizePairing(device::BluetoothDevice* device) {
-  BluetoothDevice::PairingDelegate* delegate = ShowPairingDialog(device);
-
-  // Forward AuthorizePairing to extension's pairing delegate to update the UI
-  // dialog properly.
-  if (delegate)
-    delegate->AuthorizePairing(device);
-}
-
 template <typename... Args>
 void ArcBluetoothBridge::AddAdvertisementTask(
     base::OnceCallback<void(base::OnceCallback<void(Args...)>)> task,

chrome/browser/chromeos/arc/bluetooth/arc_bluetooth_bridge.h

@@ -54,8 +54,7 @@ class ArcBluetoothBridge
       public device::BluetoothAdapter::Observer,
       public device::BluetoothAdapterFactory::AdapterCallback,
       public device::BluetoothLocalGattService::Delegate,
-      public mojom::BluetoothHost,
-      public device::BluetoothDevice::PairingDelegate {
+      public mojom::BluetoothHost {
  public:
   using GattStatusCallback =
       base::OnceCallback<void(mojom::BluetoothGattStatus)>;
@@ -307,18 +306,6 @@ class ArcBluetoothBridge
   void RemoveSdpRecord(uint32_t service_handle,
                        RemoveSdpRecordCallback callback) override;
 
-  // device::BluetoothDevice::PairingDelegate:
-  void RequestPinCode(device::BluetoothDevice* device) override;
-  void RequestPasskey(device::BluetoothDevice* device) override;
-  void DisplayPinCode(device::BluetoothDevice* device,
-                      const std::string& pincode) override;
-  void DisplayPasskey(device::BluetoothDevice* device,
-                      uint32_t passkey) override;
-  void KeysEntered(device::BluetoothDevice* device, uint32_t entered) override;
-  void ConfirmPasskey(device::BluetoothDevice* device,
-                      uint32_t passkey) override;
-  void AuthorizePairing(device::BluetoothDevice* device) override;
-
   // Set up or disable multiple advertising.
   void ReserveAdvertisementHandle(
       ReserveAdvertisementHandleCallback callback) override;
@@ -533,11 +520,6 @@ class ArcBluetoothBridge
   void SendDevice(const device::BluetoothDevice* device,
                   bool include_cached_device) const;
 
-  // Shows a pairing dialog to handle incoming pairing requests.
-  // Returns the pairing delegate of the dialog UI.
-  device::BluetoothDevice::PairingDelegate* ShowPairingDialog(
-      device::BluetoothDevice* device);
-
   ArcBridgeService* const arc_bridge_service_;  // Owned by ArcServiceManager.
 
   scoped_refptr<bluez::BluetoothAdapterBlueZ> bluetooth_adapter_;