Talkback focus doesn't move in liner order after tapping selected option in switch device panel

-Not to reflash UI to reset the focus order
-Reflash UI only when connect() is valid

Bug: 156336275
Test: make -j42 RunSettingsRoboTests
Change-Id: Ibb20252167ba13309065e4672f92cdf645661a0e

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

@@ -128,10 +128,11 @@ public class MediaDeviceUpdateWorker extends SliceBackgroundWorker
 
     public void connectDevice(MediaDevice device) {
         ThreadUtils.postOnBackgroundThread(() -> {
-            mLocalMediaManager.connectDevice(device);
+            if (mLocalMediaManager.connectDevice(device)) {
-            ThreadUtils.postOnMainThread(() -> {
+                ThreadUtils.postOnMainThread(() -> {
-                notifySliceChange();
+                    notifySliceChange();
-            });
+                });
+            }
         });
     }