vaapipostproc: 1280x720 rotated 90 and 270 degrees does not match msdkvpp or videoflip output

vaapipostproc rotation at 90 (90r) or 270 (90l) degrees modifies original YUV pixel values when resolution is 1280x720. YUV pixel values should not change when rotated. With gst-plugins-bad!640 (merged) applied to gst-plugins-bad, msdkvpp and videoflip plugins do not exhibit this issue.

1920x1080 resolution does not have this problem.

$ export LIBVA_DRIVER_NAME=iHD
$ export GST_VAAPI_ALL_DRIVERS=1

$ gst-launch-1.0 -vf videotestsrc num-buffers=10 pattern=checkers-1 \
  ! video/x-raw,format=NV12,width=1280,height=720 \
  ! vaapipostproc video-direction=90r \
  ! video/x-raw,format=NV12 \
  ! checksumsink2 dump-output=true dump-location=gst-vaapi.yuv

$ gst-launch-1.0 -vf videotestsrc num-buffers=10 pattern=checkers-1 \
  ! video/x-raw,format=NV12,width=1280,height=720 \
  ! videoflip video-direction=90r \
  ! video/x-raw,format=NV12 \
  ! checksumsink2 dump-output=true dump-location=gst-flip.yuv

$ gst-launch-1.0 -vf videotestsrc num-buffers=10 pattern=checkers-1 \
  ! video/x-raw,format=NV12,width=1280,height=720 \
  ! msdkvpp rotation=90 \
  ! video/x-raw,format=NV12 \
  ! checksumsink2 dump-output=true dump-location=gst-msdk.yuv

$ md5sum *.yuv
0d407955df198bd394ea75213f5d4d6f  gst-flip.yuv
0d407955df198bd394ea75213f5d4d6f  gst-msdk.yuv
fc784afa192be17bfcbf0b2037154896  gst-vaapi.yuv