Properly determine if a new key was added in AesDecryptor::Update()

media/cdm/aes_decryptor.h

 // Copyright 2013 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_CRYPTO_AES_DECRYPTOR_H_
 #define MEDIA_CRYPTO_AES_DECRYPTOR_H_
 
 #include <set>
 #include <string>
 
@@ skipping 108 matching lines @@
   // Creates a DecryptionKey using |key_string| and associates it with |key_id|.
   // Returns true if successful.
   bool AddDecryptionKey(const std::string& session_id,
                         const std::string& key_id,
                         const std::string& key_string);
 
   // Gets a DecryptionKey associated with |key_id|. The AesDecryptor still owns
   // the key. Returns NULL if no key is associated with |key_id|.
   DecryptionKey* GetKey(const std::string& key_id) const;
 
+  // Determines if |key_id| is already specified for |session_id|.
+  bool HasKey(const std::string& session_id, const std::string& key_id);
+
   // Deletes all keys associated with |session_id|.
   void DeleteKeysForSession(const std::string& session_id);
 
   // Callbacks for firing session events.
   SessionMessageCB session_message_cb_;
   SessionClosedCB session_closed_cb_;
   SessionKeysChangeCB session_keys_change_cb_;
 
   // Since only Decrypt() is called off the renderer thread, we only need to
   // protect |key_map_|, the only member variable that is shared between
@@ skipping 14 matching lines @@
   // Protect |new_audio_key_cb_| and |new_video_key_cb_| as they are set on the
   // main thread but called on the media thread.
   mutable base::Lock new_key_cb_lock_;
 
   DISALLOW_COPY_AND_ASSIGN(AesDecryptor);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_CRYPTO_AES_DECRYPTOR_H_