clang plugin: Remove follow-macro-expansion toggle

tools/clang/plugins/Options.h

 // 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.
 
 #ifndef TOOLS_CLANG_PLUGINS_OPTIONS_H_
 #define TOOLS_CLANG_PLUGINS_OPTIONS_H_
 
 namespace chrome_checker {
 
 struct Options {
   bool check_base_classes = false;
   bool enforce_in_pdf = false;
   bool enforce_in_thirdparty_webkit = false;  // Use in Blink code itself
   bool check_enum_last_value = false;
   bool check_templates = false;
-  bool follow_macro_expansion = false;
   // This is needed for some distributed build-sytems to respect banned
   // paths. See https://crbug.com/583454 for details.
   bool no_realpath = false;
   bool check_ipc = false;
   // Enforce that auto doesn't deduce to a raw pointer. See
   // https://crbug.com/554600 for details.
   bool check_auto_raw_pointer = false;
 };
 
 }  // namespace chrome_checker
 
 #endif  // TOOLS_CLANG_PLUGINS_OPTIONS_H_