Revert 207992: This looks like a reland of r207983, which was reverted in

trunk/src/content/common/media/midi_messages.h

Index: trunk/src/content/common/media/midi_messages.h
===================================================================
--- trunk/src/content/common/media/midi_messages.h	(revision 207994)
+++ trunk/src/content/common/media/midi_messages.h	(working copy)
@@ -1,46 +0,0 @@
-// Copyright (c) 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.
-
-// IPC messages for access to MIDI hardware.
-// Multiply-included message file, hence no include guard.
-
-#include "base/basictypes.h"
-#include "content/common/content_export.h"
-#include "ipc/ipc_message_macros.h"
-#include "media/midi/midi_port_info.h"
-
-#undef IPC_MESSAGE_EXPORT
-#define IPC_MESSAGE_EXPORT CONTENT_EXPORT
-#define IPC_MESSAGE_START MIDIMsgStart
-
-IPC_STRUCT_TRAITS_BEGIN(media::MIDIPortInfo)
-  IPC_STRUCT_TRAITS_MEMBER(id)
-  IPC_STRUCT_TRAITS_MEMBER(manufacturer)
-  IPC_STRUCT_TRAITS_MEMBER(name)
-  IPC_STRUCT_TRAITS_MEMBER(version)
-IPC_STRUCT_TRAITS_END()
-
-// Renderer request to browser for access to MIDI services.
-IPC_MESSAGE_CONTROL2(MIDIHostMsg_RequestAccess,
-                     int /* client id */,
-                     int /* access */)
-
-IPC_MESSAGE_CONTROL3(MIDIHostMsg_SendData,
-                     int /* port */,
-                     std::vector<uint8> /* data */,
-                     double /* timestamp */)
-
-// Messages sent from the browser to the renderer.
-
-IPC_MESSAGE_CONTROL5(MIDIMsg_AccessApproved,
-                     int /* client id */,
-                     int /* access */,
-                     bool /* success */,
-                     media::MIDIPortInfoList /* input ports */,
-                     media::MIDIPortInfoList /* output ports */)
-
-IPC_MESSAGE_CONTROL3(MIDIMsg_DataReceived,
-                     int /* port */,
-                     std::vector<uint8> /* data */,
-                     double /* timestamp */)