Apply automatic range checks to content enum types across IPC [content/common/media]

content/common/media/cdm_messages.h

 // Copyright 2014 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.
 
 // IPC messages for content decryption module (CDM) implementation.
 // Multiply-included message file, hence no include guard.
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "content/common/content_export.h"
 #include "content/common/media/cdm_messages_enums.h"
 #include "ipc/ipc_message_macros.h"
 #include "media/base/media_keys.h"
 #include "url/gurl.h"
 
 #undef IPC_MESSAGE_EXPORT
 #define IPC_MESSAGE_EXPORT CONTENT_EXPORT
 #define IPC_MESSAGE_START CdmMsgStart
 
 IPC_ENUM_TRAITS(media::MediaKeys::KeyError)
-IPC_ENUM_TRAITS(CdmHostMsg_CreateSession_ContentType)
+IPC_ENUM_TRAITS_MAX_VALUE(CdmHostMsg_CreateSession_ContentType,
+                          CREATE_SESSION_TYPE_LAST)
 
 // Messages from render to browser.
 
 IPC_MESSAGE_CONTROL4(CdmHostMsg_InitializeCdm,
                      int /* render_frame_id */,
                      int /* cdm_id */,
                      std::string /* key_system */,
                      GURL /* security_origin */)
 
 IPC_MESSAGE_CONTROL5(CdmHostMsg_CreateSession,
@@ skipping 37 matching lines @@
 
 IPC_MESSAGE_ROUTED2(CdmMsg_SessionClosed,
                     int /* cdm_id */,
                     uint32_t /* session_id */)
 
 IPC_MESSAGE_ROUTED4(CdmMsg_SessionError,
                     int /* cdm_id */,
                     uint32_t /* session_id */,
                     media::MediaKeys::KeyError /* error_code */,
                     uint32_t /* system_code */)