Load CMA backend from shared library

chromecast/media/base/decrypt_context.h

-// Copyright 2014 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_MEDIA_BASE_DECRYPT_CONTEXT_H_
-#define CHROMECAST_MEDIA_BASE_DECRYPT_CONTEXT_H_
-
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "chromecast/media/base/key_systems_common.h"
-
-namespace crypto {
-class SymmetricKey;
-}
-
-namespace chromecast {
-namespace media {
-
-// Base class of a decryption context: a decryption context gathers all the
-// information needed to decrypt frames with a given key id.
-// Each CDM should implement this and add fields needed to fully describe a
-// decryption context.
-//
-class DecryptContext : public base::RefCountedThreadSafe<DecryptContext> {
- public:
-  explicit DecryptContext(CastKeySystem key_system);
-
-  CastKeySystem key_system() const { return key_system_; }
-
-  // Returns the clear key if available, NULL otherwise.
-  virtual crypto::SymmetricKey* GetKey() const;
-
- protected:
-  friend class base::RefCountedThreadSafe<DecryptContext>;
-  virtual ~DecryptContext();
-
- private:
-  CastKeySystem key_system_;
-
-  DISALLOW_COPY_AND_ASSIGN(DecryptContext);
-};
-
-}  // namespace media
-}  // namespace chromecast
-
-#endif  // CHROMECAST_MEDIA_BASE_DECRYPT_CONTEXT_H_