Add command for updating the host name in WPR archive

httparchive.py

 #!/usr/bin/env python
 # Copyright 2010 Google Inc. All Rights Reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #      http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
@@ skipping 1043 matching lines @@
   elif command == 'stats':
     print http_archive.stats(options.command, options.host, options.full_path)
   elif command == 'merge':
     if not options.merged_file:
       print 'Error: Must specify a merged file name (use --merged_file)'
       return
     http_archive.merge(options.merged_file, args[2:])
   elif command == 'edit':
     http_archive.edit(options.command, options.host, options.full_path)
     http_archive.Persist(replay_file)
+  elif command == 'remap-host':
+    old_host = args[2]
+    new_host = args[3]
+    update_count = 0
+    for req in http_archive:
+      if req.host == old_host:
+        req.host = new_host
+        update_count += 1
+    updated_file_path = replay_file + '.updated'
+    http_archive.Persist(updated_file_path)
+    print 'Updated %i hosts of address %s to address %s' % (
+        update_count, old_host, new_host)
+    print 'The updated WPR is saved as %s' % updated_file_path
   else:
     option_parser.error('Unknown command "%s"' % command)
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main())