Modify fix_encodng to make it use fix_win_sys_argv for python2 only and

not for python3 on windows.

The function works around <https://bugs.python.org/issue2128>, and the bug is fixed for python3 now.

Bug: 1182016
Change-Id: I3880843b109d5b9779e5bbd1e39a3132f925ecc4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2738234
Commit-Queue: Momo Sasaki <momosasaki@google.com>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Reviewed-by: Junji Watanabe <jwata@google.com>
Reviewed-by: Takuto Ikuta <tikuta@chromium.org>

fix_encoding.py

@@ -380,6 +380,7 @@ def fix_encoding():
 
   if sys.platform == 'win32':
     encoding = sys.getdefaultencoding()
+    if sys.version_info[0] == 2:
       ret &= fix_win_sys_argv(encoding)
     ret &= fix_win_console(encoding)
   return ret