Time to remove some old APIs!

Change-Id: I73ca23b0d5c7971a00dfa05357f9b630d9b6ebc8
diff --git a/core/java/android/app/Activity.java b/core/java/android/app/Activity.java
index 5f460a2..77cbe0a 100644
--- a/core/java/android/app/Activity.java
+++ b/core/java/android/app/Activity.java
@@ -1730,6 +1730,7 @@
     /**
      * @deprecated As of {@link android.os.Build.VERSION_CODES#GINGERBREAD}
      * this is a no-op.
+     * @hide
      */
     @Deprecated
     public void setPersistent(boolean isPersistent) {