Video element with base64 encoded data URL of valid video file contents causes a media error #32645
Description
This code breaks tests: https://github.com/servo/servo/blob/main/tests/wpt/tests/html/canvas/element/manual/imagebitmap/common.sub.js#L56-L78. We get an error from gstreamer that looks like this:
0:03.16 pid:96913 [2024-06-29T16:00:09Z ERROR script::dom::htmlmediaelement] Player error: "Error from element /GstPlayBin:playbin/GstURIDecodeBin:uridecodebin0/GstDecodeBin:decodebin0/avdec_h264:avdec_h264-0: Could not decode stream.\nNo valid frames decoded before end of stream\n../gst-libs/gst/video/gstvideodecoder.c(1421): gst_video_decoder_sink_event_default (): /GstPlayBin:playbin/GstURIDecodeBin:uridecodebin0/GstDecodeBin:decodebin0/avdec_h264:avdec_h264-0:\nno valid frames found"
This is observable in tests/wpt/tests/html/canvas/element/manual/imagebitmap/createImageBitmap-invalid-args.html.