Fix state.history.parent after a state copying.
Fix state.history.parent after a state copying.

tyb0807/angr,iamahuman/angr,f-prettyland/angr,chubbymaggie/angr,iamahuman/angr,schieb/angr,tyb0807/angr,tyb0807/angr,f-prettyland/angr,iamahuman/angr,axt/angr,chubbymaggie/angr,axt/angr,schieb/angr,angr/angr,angr/angr,schieb/angr,axt/angr,f-prettyland/angr,angr/angr,chubbymaggie/angr