Trimming Opus file can result in trimmed Opus file with "Unsupported huge granule pos" errors

[Albert]

Summary of the bug:
When trimming an Opus file, with no re-encoding, the resultant trimmed Opus file can contain "Unsupported huge granule pos -xxxxxx" errors

How to reproduce:

% ffmpeg -ss 00:00:10 -to 00:00:15 -i linus.opus -codec copy ex.opus
ffmpeg version N-103279-g515e7fbce1 Copyright (c) 2000-2021 the FFmpeg developers
  built with Apple clang version 12.0.0 (clang-1200.0.32.28)
  configuration: --prefix=/usr/local --enable-gpl --enable-nonfree --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libopus --enable-libxvid --samples=fate-suite/
  libavutil      57.  4.101 / 57.  4.101
  libavcodec     59.  4.101 / 59.  4.101
  libavformat    59.  4.101 / 59.  4.101
  libavdevice    59.  0.101 / 59.  0.101
  libavfilter     8.  2.100 /  8.  2.100
  libswscale      6.  0.100 /  6.  0.100
  libswresample   4.  0.100 /  4.  0.100
  libpostproc    56.  0.100 / 56.  0.100

% ffprobe ex.opus

Patches should be submitted to the ffmpeg-devel mailing list and not this bug tracker.

[Albert]

cat linus.a* > linus.opus

[Albert]

extracted from linus.opus