Handle all possible cdm::Status values before passing through Pepper

ppapi/api/private/pp_content_decryptor.idl

 /* 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.
  */
 
 /**
  * The <code>PP_DecryptTrackingInfo</code> struct contains necessary information
  * that can be used to associate the decrypted block with a decrypt request
  * and/or an input block.
  */
@@ skipping 139 matching lines @@
 enum PP_DecryptResult {
   /** The decryption (and/or decoding) operation finished successfully. */
   PP_DECRYPTRESULT_SUCCESS = 0,
   /** The decryptor did not have the necessary decryption key. */
   PP_DECRYPTRESULT_DECRYPT_NOKEY = 1,
   /** The input was accepted by the decoder but no frame(s) can be produced. */
   PP_DECRYPTRESULT_NEEDMOREDATA = 2,
   /** An unexpected error happened during decryption. */
   PP_DECRYPTRESULT_DECRYPT_ERROR = 3,
   /** An unexpected error happened during decoding. */
-  PP_DECRYPTRESULT_DECODE_ERROR = 4
+  PP_DECRYPTRESULT_DECODE_ERROR = 4,
+  /** Session management error. */

[ddorwin, 2015/04/23 00:33:42]

I don't think we need these.

+  PP_DECRYPTRESULT_SESSION_ERROR = 5,
+  /** Decoder is not ready for initialization. */
+  PP_DECRYPTRESULT_DEFERRED_INITIALIZATION = 6
 };
 
 /**
  * <code>PP_DecryptedBlockInfo</code> struct contains the decryption result and
  * tracking info associated with the decrypted block.
  */
 [assert_size(24)]
 struct PP_DecryptedBlockInfo {
   /**
    * Result of the decryption (and/or decoding) operation.
@@ skipping 301 matching lines @@
   /**
    * Status of this key.
    */
   PP_CdmKeyStatus key_status;
 
   /**
    * Optional error code for keys that are not usable.
    */
   uint32_t system_code;
 };