Remove a useless "if" test, fix the margin affectations
Remove a useless "if" test, fix the margin affectations

prepare/TestWeasyPrint,jasco/WeasyPrint,marclaporte/WeasyPrint,prepare/TestWeasyPrint,marclaporte/WeasyPrint,andrewleech/WeasyPrint,jasco/WeasyPrint,andrewleech/WeasyPrint,Kozea/WeasyPrint,Kozea/WeasyPrint