vim: Tweak how comment nesting works
vim: Tweak how comment nesting works

Don't try to match line comments inside of a comment block. That makes
no sense and can highlight differently for people who override their
highlights.

Similarly, don't match a doc-comment inside of a comment block. It
shouldn't be highlighted differently unless it's actually a doc-comment
(and nested comments are obviously not doc comments).

Fixes #12307.

zubron/rust,P1start/rust,cllns/rust,pelmers/rust,dwillmer/rust,KokaKiwi/rust,P1start/rust,philyoon/rust,XMPPwocky/rust,AerialX/rust,nwin/rust,miniupnp/rust,aidancully/rust,pythonesque/rust,bombless/rust,dinfuehr/rust,zachwick/rust,TheNeikos/rust,defuz/rust,P1start/rust,reem/rust,omasanori/rust,krzysz00/rust,michaelballantyne/rust-gpu,AerialX/rust-rt-minimal,pshc/rust,jroesch/rust,mahkoh/rust,nwin/rust,emk/rust,mihneadb/rust,avdi/rust,miniupnp/rust,seanrivera/rust,l0kod/rust,stepancheg/rust-ide-rust,mahkoh/rust,KokaKiwi/rust,andars/rust,zaeleus/rust,victorvde/rust,KokaKiwi/rust,l0kod/rust,vhbit/rust,arthurprs/rand,pshc/rust,ebfull/rand,vhbit/rust,shepmaster/rand,defuz/rust,TheNeikos/rust,krzysz00/rust,jroesch/rust,pczarn/rust,zubron/rust,graydon/rust,avdi/rust,0x73/rust,robertg/rust,jashank/rust,emk/rust,mvdnes/rust,reem/rust,krzysz00/rust,andars/rust,bluss/rand,AerialX/rust,dwillmer/rust,zubron/rust,pczarn/rust,stepancheg/rust-ide-rust,Ryman/rust,andars/rust,victorvde/rust,avdi/rust,jashank/rust,reem/rust,GBGamer/rust,nham/rust,ktossell/rust,P1start/rust,nham/rust,krzysz00/rust,ktossell/rust,aturon/rust,pczarn/rust,servo/rust,jbclements/rust,aneeshusa/rust,quornian/rust,rohitjoshi/rust,erickt/rust,omasanori/rust,P1start/rust,0x73/rust,emk/rust,ebfull/rust,barosl/rust,andars/rust,aidancully/rust,barosl/rust,dinfuehr/rust,omasanori/rust,nham/rust,XMPPwocky/rust,aneeshusa/rust,pczarn/rust,kimroen/rust,ejjeong/rust,robertg/rust,waynenilsen/rand,hauleth/rust,emk/rust,barosl/rust,avdi/rust,GBGamer/rust,mahkoh/rust,stepancheg/rust-ide-rust,richo/rust,P1start/rust,jashank/rust,dinfuehr/rust,victorvde/rust,omasanori/rust,jbclements/rust,graydon/rust,erickt/rust,GrahamDennis/rand,GBGamer/rust,KokaKiwi/rust,XMPPwocky/rust,mvdnes/rust,pelmers/rust,aidancully/rust,zachwick/rust,zubron/rust,ejjeong/rust,krzysz00/rust,zubron/rust,jroesch/rust,nwin/rust,cllns/rust,Ryman/rust,gifnksm/rust,mdinger/rust,mdinger/rust,vhbit/rust,mahkoh/rust,robertg/rust,ebfull/rust,quornian/rust,robertg/rust,erickt/rust,GBGamer/rust,AerialX/rust,defuz/rust,avdi/rust,michaelballantyne/rust-gpu,GBGamer/rust,defuz/rust,kwantam/rust,richo/rust,pelmers/rust,pythonesque/rust,michaelballantyne/rust-gpu,pythonesque/rust,reem/rust,pythonesque/rust,untitaker/rust,jroesch/rust,andars/rust,jbclements/rust,ejjeong/rust,pczarn/rust,kimroen/rust,jbclements/rust,pelmers/rust,dwillmer/rust,jashank/rust,mvdnes/rust,nham/rust,0x73/rust,nham/rust,carols10cents/rust,AerialX/rust,gifnksm/rust,mahkoh/rust,l0kod/rust,michaelballantyne/rust-gpu,vhbit/rust,jbclements/rust,ejjeong/rust,quornian/rust,l0kod/rust,zubron/rust,aidancully/rust,servo/rust,sae-bom/rust,retep998/rand,pshc/rust,kwantam/rust,zaeleus/rust,rohitjoshi/rust,reem/rust,0x73/rust,servo/rust,aneeshusa/rust,TheNeikos/rust,stepancheg/rust-ide-rust,erickt/rust,TheNeikos/rust,carols10cents/rust,kwantam/rust,stepancheg/rust-ide-rust,untitaker/rust,mdinger/rust,barosl/rust,vhbit/rust,zaeleus/rust,Ryman/rust,mvdnes/rust,ruud-v-a/rust,dwillmer/rust,ebfull/rust,kimroen/rust,pshc/rust,bombless/rust,jashank/rust,gifnksm/rust,TheNeikos/rust,defuz/rust,aepsil0n/rust,krzysz00/rust,quornian/rust,mihneadb/rust,pshc/rust,bhickey/rand,aturon/rust,0x73/rust,kimroen/rust,richo/rust,gifnksm/rust,zachwick/rust,ejjeong/rust,GBGamer/rust,philyoon/rust,hauleth/rust,victorvde/rust,ktossell/rust,AerialX/rust-rt-minimal,nwin/rust,jashank/rust,hauleth/rust,erickt/rust,ktossell/rust,emk/rust,ruud-v-a/rust,l0kod/rust,hauleth/rust,rohitjoshi/rust,sae-bom/rust,AerialX/rust-rt-minimal,mahkoh/rust,seanrivera/rust,aneeshusa/rust,barosl/rust,aturon/rust,nwin/rust,nham/rust,mihneadb/rust,reem/rust,philyoon/rust,miniupnp/rust,dwillmer/rust,bombless/rust,miniupnp/rust,ktossell/rust,robertg/rust,pelmers/rust,mihneadb/rust,aneeshusa/rust,jbclements/rust,dwillmer/rust,nwin/rust,ruud-v-a/rust,kimroen/rust,kwantam/rust,vhbit/rust,ruud-v-a/rust,stepancheg/rust-ide-rust,hauleth/rust,bombless/rust,rohitjoshi/rust,AerialX/rust,graydon/rust,quornian/rust,ebfull/rust,miniupnp/rust,KokaKiwi/rust,omasanori/rust,ktossell/rust,cllns/rust,philyoon/rust,Ryman/rust,untitaker/rust,zachwick/rust,untitaker/rust,richo/rust,emk/rust,aturon/rust,barosl/rust,aturon/rust,pshc/rust,Ryman/rust,michaelballantyne/rust-gpu,rprichard/rust,Ryman/rust,rohitjoshi/rust,carols10cents/rust,robertg/rust,dwillmer/rust,seanrivera/rust,richo/rust,kwantam/rust,carols10cents/rust,philyoon/rust,GBGamer/rust,huonw/rand,barosl/rust,pshc/rust,rprichard/rust,rohitjoshi/rust,gifnksm/rust,l0kod/rust,michaelballantyne/rust-gpu,ebfull/rust,zaeleus/rust,ejjeong/rust,michaelballantyne/rust-gpu,graydon/rust,zubron/rust,zaeleus/rust,P1start/rust,ruud-v-a/rust,erickt/rust,mihneadb/rust,mdinger/rust,carols10cents/rust,zachwick/rust,vhbit/rust,victorvde/rust,cllns/rust,aepsil0n/rust,richo/rust,sae-bom/rust,untitaker/rust,aepsil0n/rust,omasanori/rust,miniupnp/rust,seanrivera/rust,TheNeikos/rust,quornian/rust,pelmers/rust,pczarn/rust,mihneadb/rust,pythonesque/rust,aidancully/rust,miniupnp/rust,XMPPwocky/rust,servo/rust,jroesch/rust,ktossell/rust,AerialX/rust-rt-minimal,jashank/rust,quornian/rust,rprichard/rust,0x73/rust,aepsil0n/rust,hauleth/rust,ruud-v-a/rust,pythonesque/rust,kimroen/rust,l0kod/rust,cllns/rust,philyoon/rust,mvdnes/rust,dinfuehr/rust,jbclements/rust,jroesch/rust,nham/rust,seanrivera/rust,aidancully/rust,zachwick/rust,jbclements/rust,XMPPwocky/rust,rprichard/rust,aepsil0n/rust,AerialX/rust-rt-minimal,aepsil0n/rust,vhbit/rust,GBGamer/rust,graydon/rust,bombless/rust,rprichard/rust,victorvde/rust,ebfull/rust,stepancheg/rust-ide-rust,gifnksm/rust,sae-bom/rust,0x73/rust,sae-bom/rust,seanrivera/rust,avdi/rust,dinfuehr/rust,nwin/rust,zaeleus/rust,miniupnp/rust,mvdnes/rust,jbclements/rust,aturon/rust,nwin/rust,pczarn/rust,bombless/rust,mdinger/rust,AerialX/rust,kimroen/rust,mdinger/rust,defuz/rust,KokaKiwi/rust,jroesch/rust,aneeshusa/rust,zubron/rust,untitaker/rust,emk/rust,andars/rust,bombless/rust-docs-chinese,jashank/rust,dwillmer/rust,dinfuehr/rust,AerialX/rust-rt-minimal,XMPPwocky/rust,erickt/rust,graydon/rust,Ryman/rust,achanda/rand,sae-bom/rust,carols10cents/rust,jroesch/rust,kwantam/rust,pshc/rust,cllns/rust,servo/rust,pythonesque/rust,aturon/rust,servo/rust,rprichard/rust,servo/rust,l0kod/rust