Pin fake Frame data directory modes

tests/e2e/test_media_transfer.py

@@ -9,6 +9,7 @@ class Media(harness.FrameTestCase):
     def test_upload_and_list_without_launching_a_viewer(self):
         # The transfer endpoint doesn't decode. Rendering belongs to the real
         # headset smoke checks documented in docs/vr-video.md.
+        self.assertEqual(ssh('stat -c "%U:%G %a" ~/.local/share').strip(), 'steamos:steamos 755')
         result = ok('POST', '/api/upload', raw=b'fake-media', headers={
             'X-Mode': 'media', 'X-Filename': 'test_SBS.png'})
         identity = result['id']