Encrypted Media: Use uint32 for systemCode in SessionError.

ppapi/cpp/private/content_decryptor_private.cc

 // 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.
 
 #include "ppapi/cpp/private/content_decryptor_private.h"
 
 #include <cstring>  // memcpy
 
 #include "ppapi/c/ppb_var.h"
 #include "ppapi/c/private/ppb_content_decryptor_private.h"
@@ skipping 246 matching lines @@
 
 void ContentDecryptor_Private::SessionClosed(uint32_t session_id) {
   if (has_interface<PPB_ContentDecryptor_Private>()) {
     get_interface<PPB_ContentDecryptor_Private>()->SessionClosed(
         associated_instance_.pp_instance(), session_id);
   }
 }
 
 void ContentDecryptor_Private::SessionError(uint32_t session_id,
                                             int32_t media_error,
-                                            int32_t system_code) {
+                                            uint32_t system_code) {
   if (has_interface<PPB_ContentDecryptor_Private>()) {
     get_interface<PPB_ContentDecryptor_Private>()->SessionError(
         associated_instance_.pp_instance(),
         session_id,
         media_error,
         system_code);
   }
 }
 
 void ContentDecryptor_Private::DeliverBlock(
@@ skipping 58 matching lines @@
     const PP_DecryptedSampleInfo& decrypted_sample_info) {
   if (has_interface<PPB_ContentDecryptor_Private>()) {
     get_interface<PPB_ContentDecryptor_Private>()->DeliverSamples(
         associated_instance_.pp_instance(),
         audio_frames.pp_resource(),
         &decrypted_sample_info);
   }
 }
 
 }  // namespace pp