Fix StringIO module import to be compatible with Python3

python/servo/util.py

@@ -16,7 +16,7 @@
 import shutil
 from socket import error as socket_error
 import stat
-import StringIO
+from io import BytesIO
 import sys
 import time
 import zipfile
@@ -154,7 +154,7 @@ def download(desc, src, writer, start_byte=0):
 
 
 def download_bytes(desc, src):
-    content_writer = StringIO.StringIO()
+    content_writer = BytesIO()
     download(desc, src, content_writer)
     return content_writer.getvalue()
 

python/tidy/servo_tidy/tidy.py

@@ -16,7 +16,7 @@
 import json
 import os
 import re
-import StringIO
+from io import StringIO
 import subprocess
 import sys
 
@@ -345,7 +345,7 @@ def stdout_redirect(where):
         "E501",  # 80 character line length; the standard tidy process will enforce line length
     }
 
-    output = StringIO.StringIO()
+    output = StringIO()
     with stdout_redirect(output):
         check_code(contents, ignore=ignore)
     for error in output.getvalue().splitlines():