Move ViewMsg_New to mojom

ipc/ipc.mojom

 // Copyright 2016 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.
 
 module IPC.mojom;
 
+// NOTE: This MUST match the value of MSG_ROUTING_NONE in src/ipc/ipc_message.h.
+const int32 kRoutingIdNone = -2;
+
 struct SerializedHandle {
   handle the_handle;
 
   enum Type {
     MOJO_HANDLE,
     PLATFORM_FILE,
     WIN_HANDLE,
     MACH_PORT,
   };
 
@@ skipping 11 matching lines @@
 
   // Transmits a classical Chrome IPC message.
   Receive(array<uint8> data, array<SerializedHandle>? handles);
 
   // Requests a Channel-associated interface.
   GetAssociatedInterface(string name, associated GenericInterface& request);
 };
 
 // A strictly nominal interface used to identify Channel bootstrap requests.
 interface ChannelBootstrap {};