use variadic macros/templates in IPC message implementation

base/base.gypi

 # Copyright (c) 2012 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.
 
 {
   'includes': [
     'trace_event/trace_event.gypi',
   ],
   'target_defaults': {
     'variables': {
@@ skipping 161 matching lines @@
           'debug/stack_trace.h',
           'debug/stack_trace_android.cc',
           'debug/stack_trace_posix.cc',
           'debug/stack_trace_win.cc',
           'debug/task_annotator.cc',
           'debug/task_annotator.h',
           'deferred_sequenced_task_runner.cc',
           'deferred_sequenced_task_runner.h',
           'environment.cc',
           'environment.h',
+          'export_template.h',
           'feature_list.cc',
           'feature_list.h',
           'file_descriptor_posix.h',
           'file_version_info.h',
           'file_version_info_mac.h',
           'file_version_info_mac.mm',
           'file_version_info_win.cc',
           'file_version_info_win.h',
           'files/dir_reader_fallback.h',
           'files/dir_reader_linux.h',
@@ skipping 863 matching lines @@
           'i18n/time_formatting.h',
           'i18n/timezone.cc',
           'i18n/timezone.h',
           'i18n/utf8_validator_tables.cc',
           'i18n/utf8_validator_tables.h',
         ],
       }]
     ],
   },
 }