Enforce padding parameter for AES.

Bug: 20917242
Change-Id: If1c35792279a4b03731552ced86ae7755efc6fc8
(cherry picked from commit 5bc56cdf1e466da3c3ebfeb3f49f07094d11b376)
diff --git a/google_keymaster_test_utils.cpp b/google_keymaster_test_utils.cpp
index 59e1104..c0b696d 100644
--- a/google_keymaster_test_utils.cpp
+++ b/google_keymaster_test_utils.cpp
@@ -566,6 +566,7 @@
     AuthorizationSet begin_params(client_params()), update_params, output_params;
     begin_params.push_back(TAG_NONCE, nonce.data(), nonce.size());
     begin_params.push_back(TAG_BLOCK_MODE, KM_MODE_CTR);
+    begin_params.push_back(TAG_PADDING, KM_PAD_NONE);
     string ciphertext =
         EncryptMessageWithParams(message, begin_params, update_params, &output_params);
     EXPECT_EQ(expected_ciphertext, ciphertext);