[PATCH v2 0/2] MR10583: amstream: Don't return MediaType if it hasn't changed.

[Brendan McGrath (＠redmcg)]

Windows will only include a media type on a sample if there was a change in
media type compared to the last time the buffer was retrieved.

--
  v2: amstream: Only provide MediaType on first retrieval.
      amstream/tests: Test media type is only on the first of each sample.
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/10583