Update the java doc of AndroidKeyStoreProvider#getKeyStoreOperationHandle to support Signature object

Test: m droid
Change-Id: Ie65dcfe96f3bb00cc9af4d49e4e1d1f57bde438a
diff --git a/keystore/java/android/security/keystore2/AndroidKeyStoreProvider.java b/keystore/java/android/security/keystore2/AndroidKeyStoreProvider.java
index 89d2b74..72a145f 100644
--- a/keystore/java/android/security/keystore2/AndroidKeyStoreProvider.java
+++ b/keystore/java/android/security/keystore2/AndroidKeyStoreProvider.java
@@ -151,7 +151,7 @@
      * Gets the {@link KeyStore} operation handle corresponding to the provided JCA crypto
      * primitive.
      *
-     * <p>The following primitives are supported: {@link Cipher} and {@link Mac}.
+     * <p>The following primitives are supported: {@link Cipher}, {@link Signature} and {@link Mac}.
      *
      * @return KeyStore operation handle or {@code 0} if the provided primitive's KeyStore operation
      *         is not in progress.