Issue 2120 - Add support for animations.

filters/inline_file.py

 # This file is part of the Adblock Plus website,
 # Copyright (C) 2006-2015 Eyeo GmbH
 #
 # Adblock Plus is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 3 as
 # published by the Free Software Foundation.
 #
 # Adblock Plus is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
 
-import mimetypes
+import base64
 import urllib
+from mimetypes import MimeTypes
 
 from jinja2 import contextfilter
+
+
+mime = MimeTypes()
 
 @contextfilter
 def inline_file(context, path, mime_type=None):
   if mime_type is None:
-    mime_type = mimetypes.guess_type(path)[0] or "application/octet-stream"
+    mime_type = mime.guess_type(path)[0]
+    if mime_type is None:
+      raise ValueError("Unknown mime type for file '%s', please specify." % path)
 
   source = context["source"]
   for locale in (context["locale"], "en"):
     if source.has_localizable_file(locale, path):
       file_contents = source.read_localizable_file(locale, path)
       break
   else:
     file_contents = source.read_static(path)
 
   return "data:%s;base64,%s" % (
     mime_type,
-    urllib.quote(file_contents.encode("base64"))
+    urllib.quote(base64.b64encode(file_contents))
   )