(reland) Check missing headers in the build on CQ

build/check_gn_headers.py

 #!/usr/bin/env python
 # Copyright 2017 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.
 
 """Find header files missing in GN.
 
 This script gets all the header files from ninja_deps, which is from the true
 dependency generated by the compiler, and report if they don't exist in GN.
 """
@@ skipping 145 matching lines @@
   missing = FilterOutDepsedRepo(missing, deps)
   nonexisting = FilterOutDepsedRepo(nonexisting, deps)
 
   d_p.join()
   gn_p.join()
   deps_p.join()
 
   if args.whitelist:
     whitelist = ParseWhiteList(open(args.whitelist).read())
     missing -= whitelist
+    nonexisting -= whitelist
 
   missing = sorted(missing)
   nonexisting = sorted(nonexisting)
 
   if args.json:
     with open(args.json, 'w') as f:
-      json.dump(missing, f)
+      json.dump(sorted(missing + nonexisting), f)
 
   if len(missing) == 0 and len(nonexisting) == 0:
     return 0
 
   if len(missing) > 0:
     print '\nThe following files should be included in gn files:'
     for i in missing:
       print i
 
   if len(nonexisting) > 0:
     print '\nThe following non-existing files should be removed from gn files:'
     for i in nonexisting:
       print i
 
   return 1
 
 
 if __name__ == '__main__':
   sys.exit(main())