Add OP_AUTH_NEEDED KeyStore result code

OP_AUTH_NEEDED will be returned from begin when an operation needs
a per operation authentication before calling update. Note that the
begin call succeeds when this error is returned, the token and handle
are valid.

Change-Id: I28953add4ffd7d873fc33ba3f2cf788f72b07d06

keystore/java/android/security/KeyStore.java

@@ -52,6 +52,14 @@ public class KeyStore {
     public static final int UNDEFINED_ACTION = 9;
     public static final int WRONG_PASSWORD = 10;
 
+    /**
+     * Per operation authentication is needed before this operation is valid.
+     * This is returned from {@link #begin} when begin succeeds but the operation uses
+     * per-operation authentication and must authenticate before calling {@link #update} or
+     * {@link #finish}.
+     */
+    public static final int OP_AUTH_NEEDED = 15;
+
     // Used for UID field to indicate the calling UID.
     public static final int UID_SELF = -1;