Add allocator interface for use by cdm_adapter

media/cdm/cdm_buffer.h

Index: media/cdm/cdm_buffer.h
diff --git a/media/cdm/cdm_buffer.h b/media/cdm/cdm_buffer.h
new file mode 100644
index 0000000000000000000000000000000000000000..40db8a93cd4208b8dad786864f6a7488daeb8440
--- /dev/null
+++ b/media/cdm/cdm_buffer.h
@@ -0,0 +1,30 @@
+// Copyright 2016 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_BUFFER_H_
+#define MEDIA_CDM_CDM_BUFFER_H_
+
+#include <stdint.h>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "media/base/media_export.h"
+#include "media/cdm/api/content_decryption_module.h"
+
+namespace media {
+
+class MEDIA_EXPORT CdmBuffer : public cdm::Buffer,
+                               public base::RefCountedThreadSafe<CdmBuffer> {
+ protected:
+  friend class base::RefCountedThreadSafe<CdmBuffer>;
+  CdmBuffer();
+  ~CdmBuffer() override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CdmBuffer);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_CDM_CDM_BUFFER_H_