Move EXTRA_SUBSTITUTE_APP_NAME to the published system api.

Bug: 26517701
Change-Id: I27000d777247c598cc509079004b4506ef05b404
diff --git a/api/system-current.txt b/api/system-current.txt
index c489435..36a56b6 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -5085,6 +5085,7 @@
     field public static final java.lang.String EXTRA_SHOW_CHRONOMETER = "android.showChronometer";
     field public static final java.lang.String EXTRA_SHOW_WHEN = "android.showWhen";
     field public static final java.lang.String EXTRA_SMALL_ICON = "android.icon";
+    field public static final java.lang.String EXTRA_SUBSTITUTE_APP_NAME = "android.substName";
     field public static final java.lang.String EXTRA_SUB_TEXT = "android.subText";
     field public static final java.lang.String EXTRA_SUMMARY_TEXT = "android.summaryText";
     field public static final java.lang.String EXTRA_TEMPLATE = "android.template";
diff --git a/core/java/android/app/Notification.java b/core/java/android/app/Notification.java
index dd05392..0a873d9 100644
--- a/core/java/android/app/Notification.java
+++ b/core/java/android/app/Notification.java
@@ -976,10 +976,8 @@
      */
     public static final String EXTRA_CONTAINS_CUSTOM_VIEW = "android.contains.customView";
 
-    /**
-     * @SystemApi
-     * @hide
-     */
+    /** @hide */
+    @SystemApi
     public static final String EXTRA_SUBSTITUTE_APP_NAME = "android.substName";
 
     private Icon mSmallIcon;