Add PpapiDecryptor which wraps a CDM plugin.

webkit/media/crypto/proxy_decryptor.h

 // Copyright (c) 2012 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 WEBKIT_MEDIA_CRYPTO_PROXY_DECRYPTOR_H_
 #define WEBKIT_MEDIA_CRYPTO_PROXY_DECRYPTOR_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/lock.h"
 #include "media/base/decryptor.h"
+#include "webkit/media/crypto/key_systems.h"
 
 namespace media {
 class DecryptorClient;
 }
 
 namespace webkit_media {
 
 // A decryptor proxy that creates a real decryptor object on demand and
 // forwards decryptor calls to it.
 // TODO(xhwang): Currently we don't support run-time switching among decryptor
 // objects. Fix this when needed.
 class ProxyDecryptor : public media::Decryptor {
  public:
-  explicit ProxyDecryptor(media::DecryptorClient* client);
+  explicit ProxyDecryptor(media::DecryptorClient* client,
+                          const CreatePluginCB& create_plugin_cb);
   virtual ~ProxyDecryptor();
 
   // media::Decryptor implementation.
   virtual void GenerateKeyRequest(const std::string& key_system,
                                   const uint8* init_data,
                                   int init_data_length) OVERRIDE;
   virtual void AddKey(const std::string& key_system,
                       const uint8* key,
                       int key_length,
                       const uint8* init_data,
                       int init_data_length,
                       const std::string& session_id) OVERRIDE;
   virtual void CancelKeyRequest(const std::string& key_system,
                                 const std::string& session_id) OVERRIDE;
   virtual void Decrypt(const scoped_refptr<media::DecoderBuffer>& encrypted,
                        const DecryptCB& decrypt_cb) OVERRIDE;
 
  private:
   media::DecryptorClient* const client_;
+  CreatePluginCB create_plugin_cb_;
   // Protects the |decryptor_|. The Decryptor interface specifies that the
   // Decrypt() function will be called on the decoder thread and all other
   // methods on the renderer thread. The |decryptor_| itself is thread safe
   // when this rule is obeyed. This lock is solely to prevent the race condition
   // between setting the |decryptor_| in GenerateKeyRequest() and using it in
   // Decrypt().
   base::Lock lock_;
   scoped_ptr<media::Decryptor> decryptor_;  // Protected by the |lock_|.
 
   DISALLOW_COPY_AND_ASSIGN(ProxyDecryptor);
 };
 
 }  // namespace webkit_media
 
 #endif  // WEBKIT_MEDIA_CRYPTO_PROXY_DECRYPTOR_H_