When only one device is selected in dynamic group, the device should be disabled

-Check if device id is in selected group rather than comparing client package name
-Add test cases

Bug: 154916764
Test: make -j50 RunSettingsRoboTests
Change-Id: I7364a9e3d807bbfc6b26b8212ab2da67ea329582

src/com/android/settings/media/MediaDeviceUpdateWorker.java

@@ -174,6 +174,15 @@ public class MediaDeviceUpdateWorker extends SliceBackgroundWorker
         return mLocalMediaManager.getSelectedMediaDevice();
     }
 
+    boolean isSelectedMediaDevice(MediaDevice device) {
+        for (MediaDevice selectedMediaDevice : getSelectedMediaDevice()) {
+            if (TextUtils.equals(selectedMediaDevice.getId(), device.getId())) {
+                return true;
+            }
+        }
+        return false;
+    }
+
     void adjustSessionVolume(String sessionId, int volume) {
         mLocalMediaManager.adjustSessionVolume(sessionId, volume);
     }