MountService: Send ACTION_MEDIA_UNSHARED Intent a volume is no longer shared via UMS.

Change-Id: I21c887ae76eccabcc5d8449aa0a38e98758e8958
Signed-off-by: Mike Lockwood <lockwood@android.com>
diff --git a/core/java/android/content/Intent.java b/core/java/android/content/Intent.java
index 90e8c14..179b807 100644
--- a/core/java/android/content/Intent.java
+++ b/core/java/android/content/Intent.java
@@ -1632,12 +1632,20 @@
 
     /**
      * Broadcast Action:  External media is unmounted because it is being shared via USB mass storage.
-     * The path to the mount point for the removed media is contained in the Intent.mData field.
+     * The path to the mount point for the shared media is contained in the Intent.mData field.
      */
     @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION)
     public static final String ACTION_MEDIA_SHARED = "android.intent.action.MEDIA_SHARED";
 
     /**
+     * Broadcast Action:  External media is no longer being shared via USB mass storage.
+     * The path to the mount point for the previously shared media is contained in the Intent.mData field.
+     *
+     * @hide
+     */
+    public static final String ACTION_MEDIA_UNSHARED = "android.intent.action.MEDIA_UNSHARED";
+
+    /**
      * Broadcast Action:  External media was removed from SD card slot, but mount point was not unmounted.
      * The path to the mount point for the removed media is contained in the Intent.mData field.
      */