Based on work by EAZYBLACK and Maggie for Dactyloidae commit 1414824320.
Some differences from the original work are:
- Removed the PDMWMFVP9DXVA2Preferred mediapref. This doesn't seem to work as
intended; MFT is always being used if it's enabled and available.
- Removed redundant MFT manager in WMFDecoderModule::CreateVP9Decoder
- Ensured that the MFT and DXVA2 managers in WMFDecoderModule::CreateVP9Decoder
fallback to software decoding when encountering an incompatible VP9 stream,
avoiding a repeat of #2949
- Some style consistency and code clarity changes
Job Bautista
cc1036fb34