[Nearby] Tweak BT Classic discovery to filter out BLE advertisements.

Keep BluetoothDevices discovered by BluetoothClassicMedium distinct
from BlePeripherals discovered by BleMedium.

Bug: b:154849033
Change-Id: I4f77a21b6a0f5fec29131cbc2c2d4e39d247baed
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2370093
Commit-Queue: Ryan Hansberry <hansberry@chromium.org>
Reviewed-by: James Vecore <vecore@google.com>
Cr-Commit-Position: refs/heads/master@{#801940}

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

@@ -147,6 +147,14 @@ void BluetoothClassicMedium::DeviceAdded(
     return;
   }
 
+  // Best-effort attempt to filter out BLE advertisements. BLE advertisements
+  // represented as "devices" may have their |name| set if the system has
+  // created a GATT connection to the advertiser, but all BT Classic devices
+  // that we are interested in must have their |name| set. See BleMedium
+  // for separate discovery of BLE advertisements (BlePeripherals).
+  if (!device->name)
+    return;
+
   const std::string& address = device->address;
   if (base::Contains(discovered_bluetooth_devices_map_, address)) {
     auto& bluetooth_device = discovered_bluetooth_devices_map_.at(address);

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

@@ -155,7 +155,8 @@ TEST_F(BluetoothClassicMediumTest, TestDiscovery_StartDiscoveryError) {
   EXPECT_FALSE(fake_adapter_->IsDiscoverySessionActive());
 }
 
-TEST_F(BluetoothClassicMediumTest, TestDiscovery_DeviceDiscovered) {
+TEST_F(BluetoothClassicMediumTest,
+       TestDiscovery_DeviceDiscovered_BluetoothClassicDevice) {
   StartDiscovery();
 
   NotifyDeviceAdded(kDeviceAddress1, kDeviceName1);
@@ -170,6 +171,25 @@ TEST_F(BluetoothClassicMediumTest, TestDiscovery_DeviceDiscovered) {
   StopDiscovery();
 }
 
+TEST_F(BluetoothClassicMediumTest,
+       TestDiscovery_DeviceDiscovered_BleAdvertisement) {
+  StartDiscovery();
+
+  on_device_discovered_callback_ = base::BindOnce([]() { FAIL(); });
+
+  // Do not set |name|. This reflects Chrome's usual representation of a BLE
+  // advertisement.
+  auto device_info = bluetooth::mojom::DeviceInfo::New();
+  device_info->address = kDeviceAddress1;
+  device_info->name_for_display = kDeviceAddress1;
+
+  fake_adapter_->NotifyDeviceAdded(std::move(device_info));
+
+  EXPECT_FALSE(last_device_discovered_);
+
+  StopDiscovery();
+}
+
 TEST_F(BluetoothClassicMediumTest, TestDiscovery_DeviceNameChanged) {
   StartDiscovery();