fix(frontends/lean/parser_calc): missing save calls
fix(frontends/lean/parser_calc): missing save calls

Signed-off-by: Leonardo de Moura <7610bae85f2b530654cc716772f1fe653373e892@microsoft.com>

javra/lean,soonhokong/lean-osx,avigad/lean,leodemoura/lean,levnach/lean,sp3ctum/lean,UlrikBuchholtz/lean,c-cube/lean,leodemoura/lean,UlrikBuchholtz/lean,UlrikBuchholtz/lean,soonhokong/lean,digama0/lean,fgdorais/lean,avigad/lean,leanprover/lean,levnach/lean,dselsam/lean,fgdorais/lean,fgdorais/lean,soonhokong/lean,avigad/lean,htzh/lean,javra/lean,codyroux/lean0.1,leanprover-community/lean,rlewis1988/lean,c-cube/lean,soonhokong/lean-windows,avigad/lean,soonhokong/lean,codyroux/lean0.1,dselsam/lean,fpvandoorn/lean2,johoelzl/lean,soonhokong/lean-osx,Kha/lean,soonhokong/lean-osx,sp3ctum/lean,leanprover/lean,Kha/lean,Kha/lean,c-cube/lean,javra/lean,soonhokong/travis_test,UlrikBuchholtz/lean,fpvandoorn/lean2,fpvandoorn/lean,rlewis1988/lean,johoelzl/lean,soonhokong/lean-windows,avigad/lean,htzh/lean,avigad/lean,rlewis1988/lean,dselsam/lean,leodemoura/lean,htzh/lean,leanprover/lean,leodemoura/lean,soonhokong/lean,Kha/lean,leanprover/lean,c-cube/lean,rlewis1988/lean,javra/lean,fpvandoorn/lean,dselsam/lean,htzh/lean,fpvandoorn/lean,johoelzl/lean,dselsam/lean,digama0/lean,soonhokong/lean-osx,fgdorais/lean,levnach/lean,eigengrau/lean,digama0/lean,digama0/lean,sp3ctum/lean,fgdorais/lean,sp3ctum/lean,fgdorais/lean,digama0/lean,htzh/lean,leanprover-community/lean,johoelzl/lean,UlrikBuchholtz/lean,fpvandoorn/lean,eigengrau/lean,fpvandoorn/lean,johoelzl/lean,soonhokong/travis_test,rlewis1988/lean,leanprover-community/lean,eigengrau/lean,fpvandoorn/lean2,codyroux/lean0.1,javra/lean,soonhokong/travis_test,soonhokong/lean-windows,johoelzl/lean,Kha/lean,Kha/lean,leanprover/lean,leanprover/lean,levnach/lean,leodemoura/lean,codyroux/lean0.1,leanprover-community/lean,eigengrau/lean,levnach/lean,dselsam/lean,fpvandoorn/lean2,soonhokong/lean,sp3ctum/lean,rlewis1988/lean,eigengrau/lean,fpvandoorn/lean,digama0/lean,leodemoura/lean,soonhokong/travis_test,c-cube/lean,soonhokong/lean-windows,soonhokong/lean-osx,fpvandoorn/lean2,soonhokong/lean-windows,leanprover-community/lean,leanprover-community/lean