Revert "Move input frame scaling into the recode loop"
This reverts commit 452dc215. This change has introduced a significant quality regression on content with forced key frames. (e.g. the YT and yt-hd set). It is most noticeable in static content where the kf bits dominate. Here, despite key frames being apparently coded at the same Q, there is a drop in all metrics of ~20% (e.g clXR and BFa0). Change-Id: Iba14cc61778c0846fa0a59c33c55a9fc49512cb4