Clarify type of EXTRA_DEVICE in javadoc

We have this in guide but not in javadoc, but it would make
sense to have it in javadoc as well.

Test: presubmit
Change-Id: I585248cc40c44bfa90828f04e4b5bd34694c36fd
Bug: 139376317

core/java/android/companion/CompanionDeviceManager.java

@@ -65,6 +65,13 @@ public final class CompanionDeviceManager {
     /**
      * A device, returned in the activity result of the {@link IntentSender} received in
      * {@link Callback#onDeviceFound}
+     *
+     * Type is:
+     * <ul>
+     *     <li>for classic Bluetooth - {@link android.bluetooth.BluetoothDevice}</li>
+     *     <li>for Bluetooth LE - {@link android.bluetooth.le.ScanResult}</li>
+     *     <li>for WiFi - {@link android.net.wifi.ScanResult}</li>
+     * </ul>
      */
     public static final String EXTRA_DEVICE = "android.companion.extra.DEVICE";