Add PlayerTracker and BrowserCdm interfaces.

media/base/browser_cdm.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 MEDIA_BASE_BROWSER_CDM_H_
+#define MEDIA_BASE_BROWSER_CDM_H_
+
+#include "media/base/media_keys.h"
+#include "media/base/player_tracker.h"
+
+namespace media {
+
+// Interface for browser side CDMs.
+class BrowserCdm : public MediaKeys, public PlayerTracker {
+ public:

[damienv1, 2014/05/30 15:10:15]

We should have a function to query whether a key ID is valid.
new_key_cb does not guarantee the key that is added is the one the media
pipeline is waiting for.

[xhwang, 2014/05/30 17:18:53]

Currently no CDM provides this functionality (usable key ID) yet. So I'd rather
add that later. It'll still fit in the PlayerTracker interface. WDYT?

+  BrowserCdm();

[ddorwin, 2014/05/30 20:50:05]

protected or just remove.

[xhwang, 2014/06/02 20:11:43]

Done.

+  virtual ~BrowserCdm();
+
+  // MediaKeys implementation.
+  virtual bool CreateSession(uint32 session_id,
+                             const std::string& content_type,
+                             const uint8* init_data,
+                             int init_data_length) = 0;
+  virtual void LoadSession(uint32 session_id,
+                           const std::string& web_session_id) = 0;
+  virtual void UpdateSession(uint32 session_id,
+                             const uint8* response,
+                             int response_length) = 0;
+  virtual void ReleaseSession(uint32 session_id) = 0;
+
+  // PlayerTracker implementation.
+  virtual int RegisterPlayer(const base::Closure& new_key_cb,
+                             const base::Closure& cdm_destroyed_cb) = 0;
+  virtual void UnregisterPlayer(int registration_id) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(BrowserCdm);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_BASE_BROWSER_CDM_H_