Strip was flagged for deletion in seq_transform_handle_overwrite()
on STRIP_OVERLAP_IS_FULL. Then it is removed in
SEQ_edit_strip_split() before it should be.

Handle STRIP_OVERLAP_IS_FULL in separate loop.

I think, that this is not complete solution, because in example file
overlap is caused between 2 transformed strips and one "static" in 2
different ways. Such operation should not be possible in first place.
It fixes crash at lest, so improvement in behavior can be handled
separately.