-- v4: mfreadwrite/reader: Implement IMFSourceReaderEx_GetTransformForStream. mfreadwrite/reader: Create and append a converter transform. mfreadwrite/reader: Keep the stream transforms in a list. mfreadwrite/reader: Call SetOutputType directly on the decoder transform. mf/topology_loader: Only propagate some media type attributes. mfreadwrite/reader: Split source_reader_create_decoder_for_stream helper.