Add the UNKNOWN_STRING definition to MediaStore. It will be removed
from MediaFile once I've updated the code that uses it.
diff --git a/core/java/android/provider/MediaStore.java b/core/java/android/provider/MediaStore.java
index ae53dbe2..964567a 100644
--- a/core/java/android/provider/MediaStore.java
+++ b/core/java/android/provider/MediaStore.java
@@ -179,6 +179,14 @@
     public final static String EXTRA_OUTPUT = "output";
 
     /**
+      * The string that is used when a media attribute is not known. For example,
+      * if an audio file does not have any meta data, the artist and album columns
+      * will be set to this value.
+      * @hide
+      */
+    public static final String UNKNOWN_STRING = "<unknown>";
+
+    /**
      * Common fields for most MediaProvider tables
      */