Panic if the grammar verifier sees a token it doesn't recognize
Panic if the grammar verifier sees a token it doesn't recognize

To prevent the reference grammar from getting out of sync with the real
grammar, panic if RustLexer.tokens contains an unknown token in a
similar way that verify.rs panics if it encounters an unknown binary
operation token.

jroesch/rust,pshc/rust,vhbit/rust,dwillmer/rust,omasanori/rust,andars/rust,sae-bom/rust,mihneadb/rust,pshc/rust,jashank/rust,carols10cents/rust,robertg/rust,aneeshusa/rust,GBGamer/rust,robertg/rust,nwin/rust,pelmers/rust,rohitjoshi/rust,mvdnes/rust,krzysz00/rust,XMPPwocky/rust,pelmers/rust,mihneadb/rust,KokaKiwi/rust,graydon/rust,mvdnes/rust,rohitjoshi/rust,mdinger/rust,reem/rust,TheNeikos/rust,GBGamer/rust,zachwick/rust,carols10cents/rust,nwin/rust,aidancully/rust,ejjeong/rust,seanrivera/rust,jroesch/rust,graydon/rust,XMPPwocky/rust,philyoon/rust,jroesch/rust,krzysz00/rust,mvdnes/rust,carols10cents/rust,seanrivera/rust,robertg/rust,aidancully/rust,aepsil0n/rust,pshc/rust,l0kod/rust,cllns/rust,victorvde/rust,robertg/rust,rohitjoshi/rust,KokaKiwi/rust,pshc/rust,zubron/rust,zubron/rust,jroesch/rust,nwin/rust,pshc/rust,l0kod/rust,KokaKiwi/rust,mdinger/rust,TheNeikos/rust,aepsil0n/rust,aidancully/rust,sae-bom/rust,XMPPwocky/rust,victorvde/rust,philyoon/rust,zachwick/rust,reem/rust,vhbit/rust,zubron/rust,kwantam/rust,GBGamer/rust,jashank/rust,zubron/rust,ejjeong/rust,dwillmer/rust,ejjeong/rust,ejjeong/rust,ejjeong/rust,aidancully/rust,l0kod/rust,robertg/rust,vhbit/rust,vhbit/rust,philyoon/rust,XMPPwocky/rust,mvdnes/rust,andars/rust,jashank/rust,zubron/rust,mihneadb/rust,vhbit/rust,krzysz00/rust,gifnksm/rust,pshc/rust,GBGamer/rust,nwin/rust,mdinger/rust,zachwick/rust,jroesch/rust,KokaKiwi/rust,vhbit/rust,zubron/rust,kwantam/rust,GBGamer/rust,victorvde/rust,victorvde/rust,krzysz00/rust,sae-bom/rust,ejjeong/rust,mihneadb/rust,mdinger/rust,zubron/rust,dwillmer/rust,KokaKiwi/rust,seanrivera/rust,reem/rust,pshc/rust,rohitjoshi/rust,robertg/rust,GBGamer/rust,graydon/rust,carols10cents/rust,aidancully/rust,aneeshusa/rust,gifnksm/rust,andars/rust,seanrivera/rust,zachwick/rust,TheNeikos/rust,nwin/rust,jroesch/rust,gifnksm/rust,gifnksm/rust,omasanori/rust,omasanori/rust,l0kod/rust,GBGamer/rust,l0kod/rust,zachwick/rust,vhbit/rust,jashank/rust,dwillmer/rust,reem/rust,cllns/rust,XMPPwocky/rust,philyoon/rust,victorvde/rust,omasanori/rust,andars/rust,graydon/rust,aepsil0n/rust,sae-bom/rust,pshc/rust,omasanori/rust,XMPPwocky/rust,victorvde/rust,rohitjoshi/rust,carols10cents/rust,cllns/rust,TheNeikos/rust,TheNeikos/rust,philyoon/rust,kwantam/rust,kwantam/rust,omasanori/rust,mdinger/rust,GBGamer/rust,zachwick/rust,dwillmer/rust,seanrivera/rust,l0kod/rust,nwin/rust,dwillmer/rust,kwantam/rust,krzysz00/rust,jashank/rust,jashank/rust,gifnksm/rust,andars/rust,rohitjoshi/rust,zubron/rust,l0kod/rust,aepsil0n/rust,jashank/rust,gifnksm/rust,mdinger/rust,graydon/rust,pelmers/rust,aidancully/rust,aneeshusa/rust,dwillmer/rust,pelmers/rust,dwillmer/rust,aneeshusa/rust,aneeshusa/rust,mihneadb/rust,cllns/rust,jashank/rust,krzysz00/rust,pelmers/rust,sae-bom/rust,mvdnes/rust,jroesch/rust,kwantam/rust,jroesch/rust,vhbit/rust,TheNeikos/rust,seanrivera/rust,cllns/rust,mvdnes/rust,carols10cents/rust,philyoon/rust,l0kod/rust,nwin/rust,mihneadb/rust,reem/rust,cllns/rust,graydon/rust,aepsil0n/rust,KokaKiwi/rust,andars/rust,nwin/rust,aneeshusa/rust,aepsil0n/rust,pelmers/rust,sae-bom/rust,reem/rust