Load CMA backend from shared library

chromecast/public/media/decrypt_context.h

Index: chromecast/public/media/decrypt_context.h
diff --git a/chromecast/public/media/decrypt_context.h b/chromecast/public/media/decrypt_context.h
new file mode 100644
index 0000000000000000000000000000000000000000..05e5a1a02a07b8c3f37b49ec4c5486815d6eafba
--- /dev/null
+++ b/chromecast/public/media/decrypt_context.h
@@ -0,0 +1,34 @@
+// Copyright 2015 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.
+
+#ifndef CHROMECAST_PUBLIC_MEDIA_DECRYPT_CONTEXT_H_
+#define CHROMECAST_PUBLIC_MEDIA_DECRYPT_CONTEXT_H_
+
+#include <stdint.h>
+#include <vector>
+
+#include "cast_key_system.h"
+
+namespace chromecast {
+namespace media {
+class CastDecoderBuffer;
+
+// Provides the information needed to decrypt frames.
+class DecryptContext {
+ public:
+  virtual ~DecryptContext() {}
+
+  // Get the key system to use for decryption.
+  virtual CastKeySystem GetKeySystem() = 0;
+
+  // Decrypts the given buffer.  Returns true/false for success/failure,
+  // and places the decrypted data in output if successful.
+  virtual bool Decrypt(CastDecoderBuffer* buffer,
+                       std::vector<uint8_t>* output) = 0;
+};
+
+}  // namespace media
+}  // namespace chromecast
+
+#endif  // CHROMECAST_PUBLIC_MEDIA_DECRYPT_CONTEXT_H_