Commented IDL implements statements should not generate code

Source/bindings/scripts/preprocess_idls.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 56 matching lines @@
     match = re.search(r'partial\s+interface\s+(\w+)', file_contents)
     if match:
         return match.group(1)
     return None
 
 
 # identifier-A implements identifier-B;
 # http://www.w3.org/TR/WebIDL/#idl-implements-statements
 def get_implemented_interfaces_from_idl(file_contents, interface_name):
     implemented_interfaces = []
-    for match in re.finditer(r'(\w+)\s+implements\s+(\w+)\s*;', file_contents):
+    for match in re.finditer(r'^\s*(\w+)\s+implements\s+(\w+)\s*;', file_contents, re.MULTILINE):
         # identifier-A must be the current interface
         assert match.group(1) == interface_name, \
 "Identifier on the left of the 'implements' statement should be %s in %s.idl, but found %s" % (interface_name, interface_name, match.group(1))
         implemented_interfaces.append(match.group(2))
     return implemented_interfaces
 
 def is_callback_interface_from_idl(file_contents):
     match = re.search(r'callback\s+interface\s+\w+', file_contents)
     return match is not None
 
@@ skipping 150 matching lines @@
     idl_files = []
     with open(options.idl_files_list) as idl_files_list_file:
         for line in idl_files_list_file:
             idl_files.append(string.rstrip(line, '\n'))
     resolved_supplementals = parse_idl_files(idl_files, options.window_constructors_file, options.workercontext_constructors_file)
     write_dependency_file(options.supplemental_dependency_file, resolved_supplementals, only_if_changed=options.write_file_only_if_changed)
 
 
 if __name__ == '__main__':
     main()