gn docs generator: Don't get confused by ansi escape codes.

tools/gn/bin/help_as_html.py

 #!/usr/bin/env python
 # Copyright 2014 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.
 
 # Runs 'gn help' and various subhelps, and spits out html.
 # TODO:
 # - Handle numbered and dashed lists -> <ol> <ul>. (See "os" and "toolchain").
 # - Handle "Arguments:" blocks a bit better (the argument names could be
 #   distinguished).
 # - Convert "|blahblah|" to <code>.
 # - Spit out other similar formats like wiki, markdown, whatever.
 
 import cgi
+import re
 import subprocess
 import sys
 
 
 def GetOutput(*args):
   try:
-    return subprocess.check_output([sys.argv[1]] + list(args))
+    # TODO: Remove ansi escape code stripping if crbug.com/362239 gets fixed.
+    ansi_escape = re.compile(r'\x1b[^m]*m')
+    return ansi_escape.sub(
+        '', subprocess.check_output([sys.argv[1]] + list(args)))
   except subprocess.CalledProcessError:
     return ''
 
 
 def ParseTopLevel(out):
   commands = []
   output = []
   for line in out.splitlines():
     if line.startswith('  '):
       command, sep, rest = line.partition(':')
@@ skipping 64 matching lines @@
   footer = '</div></body></html>'
   commands, output = ParseTopLevel(GetOutput('help'))
   for command in commands:
     output += ParseCommand(command, GetOutput('help', command))
   print header + '\n'.join(output) + footer
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main())