Mirko Bonadei be23ea4bb9 Revert "Make frame transformer MimeType pure virtual again"
This reverts commit 3ea9fc4cd8135555360aafbfe788571d9e2f23f9.

Reason for revert: Breaks downstream project.

Original change's description:
> Make frame transformer MimeType pure virtual again
>
> after both audio and video have been implemented.
>
> BUG=webrtc:15579
>
> Change-Id: Ib52e8f67292259cbf7497a884672de72f3003282
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/326162
> Commit-Queue: Philipp Hancke <phancke@microsoft.com>
> Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> Reviewed-by: Tony Herre <herre@google.com>
> Cr-Commit-Position: refs/heads/main@{#41114}

BUG=webrtc:15579
No-Presubmit: true
No-Tree-Checks: true
No-Try: true

Change-Id: I9b4c9753e260aca98d24a40f32ce57d86a181ea2
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/326525
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41116}
2023-11-09 14:24:53 +00:00
..
2023-03-21 16:54:19 +00:00