Encrypted Media: Allows empty key message to be fired.

ppapi/c/private/ppb_content_decryptor_private.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.
  */
 
 /* From private/ppb_content_decryptor_private.idl,
- *   modified Fri Oct 26 14:47:38 2012.
+ *   modified Tue Dec  4 10:30:29 2012.
  */
 
 #ifndef PPAPI_C_PRIVATE_PPB_CONTENT_DECRYPTOR_PRIVATE_H_
 #define PPAPI_C_PRIVATE_PPB_CONTENT_DECRYPTOR_PRIVATE_H_
 
 #include "ppapi/c/pp_bool.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_macros.h"
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/c/pp_stdint.h"
@@ skipping 88 matching lines @@
    * <code>AddKey()</code> and <code>KeyMessage()</code> calls required to
    * prepare for decryption.
    *
    * @param[in] key_system A <code>PP_Var</code> of type
    * <code>PP_VARTYPE_STRING</code> containing the name of the key system.
    *
    * @param[in] session_id A <code>PP_Var</code> of type
    * <code>PP_VARTYPE_STRING</code> containing the session ID.
    *
    * @param[in] resource A <code>PP_Resource</code> corresponding to a
-   * <code>PPB_Buffer_Dev</code> resource that contains the message.
+   * <code>PPB_Buffer_Dev</code> resource that contains the message. A 0
+   * resource is allowed which indicates an empty message.
    *
    * @param[in] default_url A <code>PP_Var</code> of type
    * <code>PP_VARTYPE_STRING</code> containing the default URL for the message.
    */
   void (*KeyMessage)(PP_Instance instance,
                      struct PP_Var key_system,
                      struct PP_Var session_id,
                      PP_Resource message,
                      struct PP_Var default_url);
   /**
@@ skipping 130 matching lines @@
       const struct PP_DecryptedBlockInfo* decrypted_block_info);
 };
 
 typedef struct PPB_ContentDecryptor_Private_0_6 PPB_ContentDecryptor_Private;
 /**
  * @}
  */
 
 #endif  /* PPAPI_C_PRIVATE_PPB_CONTENT_DECRYPTOR_PRIVATE_H_ */