Revert "[ot-shape-normalize] Move buffer out of hb_ot_shape_normalize_context_t" This reverts commit 8cdbea5580731c2bf66e56bf619c1fbb2978692e. For some reason this is causing several tests to crash locally for me (on macOS), see: https://github.com/harfbuzz/harfbuzz/commit/8cdbea5580731c2bf66e56bf619c1fbb2978692e#commitcomment-55898088