Prevent the screen reader box from unexpected scrolling in dream setting

page.

Bug: 228355186
Test: manual
Change-Id: I66a70d6b12bd3a2766e6879cb27c68a851d1dd87
Merged-In: I66a70d6b12bd3a2766e6879cb27c68a851d1dd87
(cherry picked from commit edfd262be2)

src/com/android/settings/dream/DreamSettings.java

@@ -195,6 +195,10 @@ public class DreamSettings extends DashboardFragment implements OnMainSwitchChan
         mPreviewButton.setOnClickListener(v -> dreamBackend.preview(dreamBackend.getActiveDream()));
 
         mRecyclerView = super.onCreateRecyclerView(inflater, parent, bundle);
+        // The enable/disable status change of the nested RecyclerView(Dream Picker) causes the
+        // focus moving. Make the RecyclerView unfocusable to prevent the unexpected scrolling when
+        // the focus changes in the TalkBack mode.
+        mRecyclerView.setFocusable(false);
         updatePaddingForPreviewButton();
         return mRecyclerView;
     }