[tests] use "h264" instead of "libx264" for tests (fixes: #951)

[jlaine]

This allows running the test suite against FFmpeg builds which do not have libx264 enabled.

[jlaine]

@deepsworld this one is for you. Changing "libx264" to "h264" doesn't seem to break the test suite if libx264 is available. I also tried removing libx264 support from our FFmpeg, but then things do start to break

[jlaine]

I think I'm most likely going to close this issue, it doesn't actually solve anything..

[hmaarrfk]

I think you need a few more patches: https://github.com/conda-forge/av-feedstock/blob/main/recipe/lgpl_tests.patch

[hmaarrfk]

For more clarity, we at a conda-forge now build ffmpeg with (gpl) and without (lgpl) x264.

We then compile pyav with lgpl, and then test it with the gpl and the lgpl versions. Without the patch I linked to, the lgpl-only tests would fail.

[hmaarrfk]

Nevermind, it seems that your patch is good. It actually includes the addition 5 line cleanup that I didn't include in mine due to not wanting to touch too many lines of code.

Did you build your FFMPEG builds with openh264? I'm happy to test the patch at conda-forge (where we have lgpl builds readily available).

[jlaine]

As previously stated I think we should close this PR.