Add attestation support to keystore.

Bug: 22914603
Change-Id: I14fbfbe30b96c5c29278fa548e06b65f15942fe2
diff --git a/keystore/key_store_service.h b/keystore/key_store_service.h
index e61bdea..35b8928 100644
--- a/keystore/key_store_service.h
+++ b/keystore/key_store_service.h
@@ -114,6 +114,9 @@
 
     int32_t addAuthToken(const uint8_t* token, size_t length);
 
+    int32_t attestKey(const String16& name, const KeymasterArguments& params,
+                      KeymasterCertificateChain* outChain) override;
+
   private:
     static const int32_t UID_SELF = -1;