This broke lots of layout tests on OSX.

tools/data_pack/repack.py

Index: tools/data_pack/repack.py
===================================================================
--- tools/data_pack/repack.py	(revision 101223)
+++ tools/data_pack/repack.py	(working copy)
@@ -20,30 +20,18 @@
   """Write a new data pack to |output_file| based on a list of filenames
   (|input_files|)"""
   resources = {}
-  encoding = None
   for filename in input_files:
-    new_content = data_pack.ReadDataPack(filename)
+    new_resources = data_pack.ReadDataPack(filename)
 
     # Make sure we have no dups.
-    duplicate_keys = set(new_content.resources.keys()) & set(resources.keys())
+    duplicate_keys = set(new_resources.keys()) & set(resources.keys())
     if len(duplicate_keys) != 0:
       raise exceptions.KeyError("Duplicate keys: " + str(list(duplicate_keys)))
 
-    # Make sure encoding is consistent.
-    if encoding in (None, data_pack.BINARY):
-      encoding = new_content.encoding
-    elif new_content.encoding not in (data_pack.BINARY, encoding):
-        raise exceptions.KeyError("Inconsistent encodings: " +
-                                  str(encoding) + " vs " +
-                                  str(new_content.encoding))
+    resources.update(new_resources)
 
-    resources.update(new_content.resources)
+  data_pack.WriteDataPack(resources, output_file)
 
-  # Encoding is 0 for BINARY, 1 for UTF8 and 2 for UTF16
-  if encoding is None:
-    encoding = data_pack.BINARY
-  data_pack.WriteDataPack(resources, output_file, encoding)
-
 def main(argv):
   if len(argv) < 3:
     print ("Usage:\n  %s <output_filename> <input_file1> [input_file2] ... " %