[NearbyShare] Reimplement BTMedium's FindRemoteDevice as GetRemoteDevice

BluetoothMediumClassic::GetRemoteDevice should now return a new device
with the given mac address if one hasn't been added yet.

Bug: 1131981
Test: unit_tests
Change-Id: I5a8f19469799074e667bfa05f3ae667d789d8572
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2435821
Commit-Queue: Curt Clemens <cclem@google.com>
Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811411}

chrome/services/sharing/nearby/platform_v2/bluetooth_classic_medium.cc

@@ -73,15 +73,7 @@ bool BluetoothClassicMedium::StopDiscovery() {
 std::unique_ptr<api::BluetoothSocket> BluetoothClassicMedium::ConnectToService(
     api::BluetoothDevice& remote_device,
     const std::string& service_uuid) {
-  // TODO(hansberry): This currently assumes that the device was discovered via
-  // Bluetooth Classic (the remote device is in high visibility mode), meaning
-  // this address is the expected permanent BT MAC address. Once an
-  // implementation is in place to scan for devices over BLE, a new mechanism
-  // to query for the remote device's permanent BT MAC address from stored
-  // certificates will be needed.
-  // We provided this |remote_device|, so we can safely downcast it.
-  const std::string& address =
-      static_cast<chrome::BluetoothDevice&>(remote_device).GetAddress();
+  const std::string& address = remote_device.GetMacAddress();
 
   bluetooth::mojom::ConnectToServiceResultPtr result;
   bool success = adapter_->ConnectToServiceInsecurely(
@@ -114,7 +106,18 @@ BluetoothClassicMedium::ListenForService(const std::string& service_name,
 BluetoothDevice* BluetoothClassicMedium::GetRemoteDevice(
     const std::string& mac_address) {
   auto it = discovered_bluetooth_devices_map_.find(mac_address);
-  return it == discovered_bluetooth_devices_map_.end() ? nullptr : &it->second;
+  if (it != discovered_bluetooth_devices_map_.end())
+    return &it->second;
+
+  // If a device with |mac_address| has not been found, Nearby Connections
+  // is attempting to connect to a device with |mac_adress| which is not
+  // discoverable. Create a placeholder BluetoothDevice to be used by
+  // ConnectToService().
+  bluetooth::mojom::DeviceInfoPtr device = bluetooth::mojom::DeviceInfo::New();
+  device->address = mac_address;
+  return &discovered_bluetooth_devices_map_
+              .emplace(mac_address, std::move(device))
+              .first->second;
 }
 
 void BluetoothClassicMedium::PresentChanged(bool present) {

chrome/services/sharing/nearby/platform_v2/bluetooth_classic_medium_unittest.cc

@@ -156,11 +156,17 @@ TEST_F(BluetoothClassicMediumTest, TestDiscovery_StartDiscoveryError) {
 }
 
 TEST_F(BluetoothClassicMediumTest,
-       TestDiscovery_DeviceDiscovered_BluetoothClassicDevice) {
+       TestDiscovery_GetRemoteDevice_GetUndiscovered) {
   StartDiscovery();
 
-  ASSERT_FALSE(bluetooth_classic_medium_->GetRemoteDevice(kDeviceAddress1));
-  ASSERT_FALSE(bluetooth_classic_medium_->GetRemoteDevice(kDeviceAddress2));
+  EXPECT_TRUE(bluetooth_classic_medium_->GetRemoteDevice(kDeviceAddress1));
+
+  StopDiscovery();
+}
+
+TEST_F(BluetoothClassicMediumTest,
+       TestDiscovery_DeviceDiscovered_BluetoothClassicDevice) {
+  StartDiscovery();
 
   NotifyDeviceAdded(kDeviceAddress1, kDeviceName1);
   EXPECT_TRUE(bluetooth_classic_medium_->GetRemoteDevice(kDeviceAddress1));

chrome/services/sharing/nearby/platform_v2/bluetooth_device.cc

@@ -18,11 +18,6 @@ std::string BluetoothDevice::GetName() const {
 }
 
 std::string BluetoothDevice::GetMacAddress() const {
-  // TODO(hansberry): Implement.
-  return std::string();
-}
-
-std::string BluetoothDevice::GetAddress() const {
   return device_info_->address;
 }
 

chrome/services/sharing/nearby/platform_v2/bluetooth_device.h

@@ -27,7 +27,6 @@ class BluetoothDevice : public api::BluetoothDevice {
   std::string GetName() const override;
   std::string GetMacAddress() const override;
 
-  std::string GetAddress() const;
   void UpdateDeviceInfo(bluetooth::mojom::DeviceInfoPtr device_info);
 
  private: