[TIAF] Fix ClassCastException of content rating

Test: mmm
Bug: 366132585
Flag: EXEMPT bugfix
Change-Id: Iedc9decc4cb2516fd534ef62a26dd78af430155d
diff --git a/media/java/android/media/tv/interactive/ITvInteractiveAppSessionWrapper.java b/media/java/android/media/tv/interactive/ITvInteractiveAppSessionWrapper.java
index ec6c2bf..8e6297c 100644
--- a/media/java/android/media/tv/interactive/ITvInteractiveAppSessionWrapper.java
+++ b/media/java/android/media/tv/interactive/ITvInteractiveAppSessionWrapper.java
@@ -267,7 +267,9 @@
                 break;
             }
             case DO_NOTIFY_CONTENT_BLOCKED: {
-                mSessionImpl.notifyContentBlocked((TvContentRating) msg.obj);
+                String contentRating = (String) msg.obj;
+                mSessionImpl.notifyContentBlocked(
+                        TvContentRating.unflattenFromString(contentRating));
                 break;
             }
             case DO_NOTIFY_SIGNAL_STRENGTH: {