Use the RPC channel to set the ID <-> handle mapping....

ceee/ie/common/constants.cc

 // Copyright (c) 2010 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.
 //
 // Shared constants between the different modules of CEEE.
 
 #include "ceee/ie/common/constants.h"
 
 namespace ceee_event_names {
   const char kCeeeOnTabUnmapped[] = "ceee.OnTabUnmapped";
+  const char kCeeeMapTabIdToHandle[] = "ceee.MapTabIdToHandle";
+  const char kCeeeMapToolbandIdToHandle[] = "ceee.MapToolbandIdToHandle";
 }