[FIX] web: attachment with safari

With Safari, the function content_disposition must return "attachment; filename=\"%s\"" % filename
to avoid that Werkzeug raises an UnicodeDecodeError.

Fixes #6160
opw:634205

addons/web/controllers/main.py

@@ -527,7 +527,7 @@ def content_disposition(filename, req):
     if browser == 'msie' and version < 9:
         return "attachment; filename=%s" % escaped
     elif browser == 'safari':
-        return "attachment; filename=%s" % filename
+        return "attachment; filename=\"%s\"" % filename
     else:
         return "attachment; filename*=UTF-8''%s" % escaped