Revert "Copy&Paste errors"

This reverts commit a1b7b8485975429bad2c4ddc7e79883367c342fe.
Revert "Fixed pathspec_t::operator=() semantics when assigning to itself."

This reverts commit bcb4ee0858e4d07493a9284ffbc83def8038327f.
Delay deletion of pathspec_t fields in pathspec_t::operator=