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/oemcrypto/util/oec_ref_util.gyp

@@ -0,0 +1,20 @@
+# Copyright 2022 Google LLC. All Rights Reserved. This file and proprietary
+# source code may only be used and distributed under the Widevine
+# License Agreement.
+{
+  'variables': {
+    'oemcrypto_dir': '..',
+    'util_dir': '../../util',
+  },
+  'targets': [
+    {
+      'target_name': 'oec_ref_util',
+      'type': 'static_library',
+      'standalone_static_library': 1,
+      'hard_dependency': 1,
+      'includes': [
+        'oec_ref_util.gypi',
+      ],
+    },
+  ],
+}