Output switcher shows the device list by an incorrect package name

-Reset package name when it is different with previous one
-Add test case

Bug: 156561856
Test: make -j50 RunSettingsRoboTests
Change-Id: I7931ebbc59ab404f12473fe29f2735ad3a8197fd

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

@@ -73,7 +73,8 @@ public class MediaDeviceUpdateWorker extends SliceBackgroundWorker
     protected void onSlicePinned() {
         mMediaDevices.clear();
         mIsTouched = false;
-        if (mLocalMediaManager == null) {
+        if (mLocalMediaManager == null || !TextUtils.equals(mPackageName,
+                mLocalMediaManager.getPackageName())) {
             mLocalMediaManager = new LocalMediaManager(mContext, mPackageName, null);
         }