Support non-ASCII GNUPGHOME environment variable

Here we don't need to encode this gpg_dir string when using
Python 2.7 on Linux.

Change-Id: I56724e9511d3b1aea61535e654a45c212130630d

repo

@@ -432,7 +432,10 @@ def SetupGnuPG(quiet):
       sys.exit(1)
 
   env = os.environ.copy()
-  env['GNUPGHOME'] = gpg_dir.encode()
+  try:
+    env['GNUPGHOME'] = gpg_dir
+  except UnicodeEncodeError:
+    env['GNUPGHOME'] = gpg_dir.encode()
 
   cmd = ['gpg', '--import']
   try:
@@ -638,7 +641,10 @@ def _Verify(cwd, branch, quiet):
       _print(file=sys.stderr)
 
   env = os.environ.copy()
-  env['GNUPGHOME'] = gpg_dir.encode()
+  try:
+    env['GNUPGHOME'] = gpg_dir
+  except UnicodeEncodeError:
+    env['GNUPGHOME'] = gpg_dir.encode()
 
   cmd = [GIT, 'tag', '-v', cur]
   proc = subprocess.Popen(cmd,