Extract CdmManager from MojoCdmService.

media/cdm/cdm_manager.h

+// Copyright 2017 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 MEDIA_CDM_CDM_MANAGER_H_
+#define MEDIA_CDM_CDM_MANAGER_H_
+
+#include <map>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/synchronization/lock.h"
+#include "media/base/media_export.h"
+
+namespace media {
+
+class ContentDecryptionModule;
+
+// Provides a singleton registry of CDM instances. This is used to share
+// ContentDecryptionModules between the MojoMediaService and
+// AndroidVideoDecodeAccelerator, and should be removed along with AVDA in the
+// future. (MojoCdmServiceContext serves the same purpose for Media Mojo
+// services, but scoped to a single InterfaceFactory.)
+class MEDIA_EXPORT CdmManager {
+ public:
+  CdmManager();
+  ~CdmManager();
+
+  static CdmManager* GetInstance();
+
+  // Returns the CDM associated with |cdm_id|. Can be called on any thread.
+  scoped_refptr<ContentDecryptionModule> GetCdm(int cdm_id);
+
+  // Registers the |cdm| for |cdm_id|.
+  void RegisterCdm(int cdm_id, scoped_refptr<ContentDecryptionModule> cdm);
+
+  // Unregisters the CDM associated with |cdm_id|.
+  void UnregisterCdm(int cdm_id);
+
+ private:
+  base::Lock lock_;
+  std::map<int, scoped_refptr<ContentDecryptionModule>> cdm_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(CdmManager);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_CDM_CDM_MANAGER_H_