Revert r374665: "[lit] Try yet again to fix new tests that fail on Windows bots"

This series of patches still breaks a Windows bot.

llvm-svn: 374677

utils/lit/lit/builtin_commands/diff.py

@@ -95,9 +95,6 @@ def compareTwoTextFiles(flags, filepaths, filelines_bin, encoding):
     func = difflib.unified_diff if flags.unified_diff else difflib.context_diff
     for diff in func(filelines[0], filelines[1], filepaths[0], filepaths[1],
                      n = flags.num_context_lines):
-        if hasattr(diff, 'decode'):
-            # python 2.7
-            diff = diff.decode()
         sys.stdout.write(diff)
         exitCode = 1
     return exitCode