[Extensions] Determine NativeMessaging ID solely on the browser process

extensions/common/extension_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 extensions.
 // Multiply-included message file, hence no include guard.
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 650 matching lines @@
 // the given ID.  This always returns a valid port ID which can be used for
 // sending messages.  If an error occurred, the opener will be notified
 // asynchronously.
 IPC_SYNC_MESSAGE_CONTROL4_1(ExtensionHostMsg_OpenChannelToExtension,
                             int /* frame_routing_id */,
                             ExtensionMsg_ExternalConnectionInfo,
                             std::string /* channel_name */,
                             bool /* include_tls_channel_id */,
                             int /* port_id */)
 
-IPC_SYNC_MESSAGE_CONTROL3_1(ExtensionHostMsg_OpenChannelToNativeApp,
+IPC_SYNC_MESSAGE_CONTROL2_1(ExtensionHostMsg_OpenChannelToNativeApp,
                             int /* frame_routing_id */,
-                            std::string /* source_extension_id */,
                             std::string /* native_app_name */,
                             int /* port_id */)
 
 // Get a port handle to the given tab.  The handle can be used for sending
 // messages to the extension.
 IPC_SYNC_MESSAGE_CONTROL4_1(ExtensionHostMsg_OpenChannelToTab,
                             int /* frame_routing_id */,
                             ExtensionMsg_TabTargetConnectionInfo,
                             std::string /* extension_id */,
                             std::string /* channel_name */,
@@ skipping 147 matching lines @@
                     int /* acc_obj_id */,
                     base::string16 /* selector */)
 
 // Result of a query selector request.
 // result_acc_obj_id is the accessibility tree ID of the result element; 0
 // indicates no result.
 IPC_MESSAGE_ROUTED3(ExtensionHostMsg_AutomationQuerySelector_Result,
                     int /* request_id */,
                     ExtensionHostMsg_AutomationQuerySelector_Error /* error */,
                     int /* result_acc_obj_id */)