Fix content description for notification icons

Change-Id: Icb4c6d8a77211d0c8922e28958609a332b19dfcc
Fixes: 27552350
diff --git a/core/java/android/app/Notification.java b/core/java/android/app/Notification.java
index 39f8e19..ce49b1c 100644
--- a/core/java/android/app/Notification.java
+++ b/core/java/android/app/Notification.java
@@ -3301,7 +3301,10 @@
             }
         }
 
-        private String loadHeaderAppName() {
+        /**
+         * @hide
+         */
+        public String loadHeaderAppName() {
             CharSequence name = null;
             final PackageManager pm = mContext.getPackageManager();
             if (mN.extras.containsKey(EXTRA_SUBSTITUTE_APP_NAME)) {