Initial v16 ODK Library

This commit has the initial ODK library.  Partners may use this code
to begin integrating the ODK library into their platform.  The
functionality is not complete, but this should help partners get an
early start playing with build files.

util/include/arraysize.h

@@ -0,0 +1,20 @@
+// Copyright 2019 Google LLC. All Rights Reserved. This file and proprietary
+// source code may only be used and distributed under the Widevine Master
+// License Agreement.
+
+#ifndef WVCDM_UTIL_ARRAYSIZE_H_
+#define WVCDM_UTIL_ARRAYSIZE_H_
+
+#include <stdint.h>
+
+namespace wvcdm {
+
+// Returns the size of a fixed-length array.
+template <typename T, size_t N>
+constexpr size_t ArraySize(const T (&)[N]) {
+  return N;
+}
+
+}  // namespace wvcdm
+
+#endif  // WVCDM_UTIL_ARRAYSIZE_H_