Add allocator interface for use by cdm_adapter

media/cdm/cdm_allocator.h

Index: media/cdm/cdm_allocator.h
diff --git a/media/cdm/cdm_allocator.h b/media/cdm/cdm_allocator.h
new file mode 100644
index 0000000000000000000000000000000000000000..8d14311aa1b982d83d3651d05c11cfb5d23137b2
--- /dev/null
+++ b/media/cdm/cdm_allocator.h
@@ -0,0 +1,42 @@
+// 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_ALLOCATOR_H_
+#define MEDIA_CDM_CDM_ALLOCATOR_H_
+
+#include <stdint.h>
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "media/base/media_export.h"
+
+namespace cdm {
+class Buffer;
+}
+
+namespace media {
+
+class VideoFrameImpl;
+
+class MEDIA_EXPORT CdmAllocator {
+ public:
+  virtual ~CdmAllocator();
+
+  // Allocates a buffer with at least |capacity| bytes. Caller is required to
+  // call Destroy() on the returned buffer when it is done with it.
+  virtual cdm::Buffer* Allocate(uint32_t capacity) = 0;

[xhwang, 2016/02/12 08:45:30]

nit: "Allocate" is from existing code. But it seems this should really be
CreateCdmBuffer(), given we also have CreateCdmVideoFrame(). Feel free to ignore
this comment though since naming is hard ;)

[jrummell, 2016/02/12 23:14:20]

I like the consistency. Done.

+
+  // Returns a new VideoFrameImpl.
+  virtual scoped_ptr<VideoFrameImpl> CreateCdmVideoFrame() = 0;
+
+ protected:
+  CdmAllocator();
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CdmAllocator);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_CDM_CDM_ALLOCATOR_H_