734a9dec43
Caused by 598af45459
Above commit added respect for the NLA strip offset (rightfully so, by
using `ANIM_nla_mapping_apply_fcurve`).
However, when no closest frame was found, the code moved on to the next
FCurve without restoring to the original FCurve --
`ANIM_nla_mapping_apply_fcurve` needs to be called in pairs.
To resolve, now always restore to the original FCurve.
Pull Request: https://projects.blender.org/blender/blender/pulls/121483