Cast: Added support for AES-CTR crypto.

media/cast/test/crypto_utility.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/strings/string_number_conversions.h"
+#include "media/cast/test/crypto_utility.h"
+
+namespace media {
+namespace cast {
+
+std::string ConvertFromBase16String(const std::string base_16) {
+  std::string compressed;
+  DCHECK_EQ(base_16.size() % 2, 0u) << "Must be a multiple of 2";
+  compressed.reserve(base_16.size() / 2);
+
+  std::vector<uint8> v;
+  if (!base::HexStringToBytes(base_16, &v)) {
+    NOTREACHED();
+  }
+  compressed.assign(reinterpret_cast<const char*>(&v[0]), v.size());
+  return compressed;
+}
+
+}  // namespace cast
+}  // namespace media