Cherry pick 18.4 changes to udc-widevine-dev

Get the udc-widevine-dev Android branch and oemcrypto-v18 cdm branch in
sync. The commit ID for 18.4 on oemcrypto-v18 is
a2f23a2281e5e06dc2867585bdc516fa132b6396.

Merged from go/wvgerrit/190151

Bug: 290252845
Test: WVTS tests are running and passing
Change-Id: I457332e7ca70a5b5169345e1279b3eb9f18413b6

libwvdrmengine/cdm/test/cdm_test_runner.h

@@ -0,0 +1,20 @@
+// Copyright 2021 Google LLC. All Rights Reserved. This file and proprietary
+// source code may only be used and distributed under the Widevine License
+// Agreement.
+
+#ifndef WVCDM_CDM_TEST_CDM_TEST_RUNNER_H_
+#define WVCDM_CDM_TEST_CDM_TEST_RUNNER_H_
+
+#include <iostream>
+#include "cdm.h"
+
+namespace widevine {
+// Run all CDM tests using the specified storage, clock, and timer. It parses
+// standard command line arguments, sets some default test client info,
+// initializes a CDM object, and then runs all the tests.
+// Returns 0 on success.
+int Main(Cdm::IStorage* storage, Cdm::IClock* clock, Cdm::ITimer* timer,
+         Cdm::ILogger* logger, int argc, char** argv);
+}  // namespace widevine
+
+#endif  // WVCDM_CDM_TEST_CDM_TEST_RUNNER_H_