Auto merge of #16281 - servo:atomic_opaque, r=heycam
Auto merge of #16281 - servo:atomic_opaque, r=heycam

Add std::atomic to opaque_types in build_gecko

Recent change in bug 1277709 makes ThreadSafeAutoRefCnt start using std::atomic, which somehow doesn't not have #[derive(Debug)] on Windows, which makes all objects which includes ThreadSafeAutoRefCnt to stop having #[derive(Debug)]. This breaks stylo build on Windows.

By adding it as an opaque type, std::atomic would derive Debug again.

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anthgur/servo,emilio/servo,anthgur/servo,upsuper/servo,CJ8664/servo,notriddle/servo,cbrewster/servo,emilio/servo,ConnorGBrewster/servo,CJ8664/servo,canaltinova/servo,upsuper/servo,nnethercote/servo,larsbergstrom/servo,fiji-flo/servo,canaltinova/servo,SimonSapin/servo,saneyuki/servo,KiChjang/servo,pyfisch/servo,sadmansk/servo,szeged/servo,mbrubeck/servo,peterjoel/servo,notriddle/servo,eddyb/servo,KiChjang/servo,rnestler/servo,thiagopnts/servo,dsandeephegde/servo,larsbergstrom/servo,pyfisch/servo,upsuper/servo,avadacatavra/servo,peterjoel/servo,sadmansk/servo,cbrewster/servo,eddyb/servo,canaltinova/servo,splav/servo,mbrubeck/servo,dsandeephegde/servo,pyfisch/servo,saneyuki/servo,avadacatavra/servo,fiji-flo/servo,splav/servo,upsuper/servo,anthgur/servo,eddyb/servo,SimonSapin/servo,eddyb/servo,pyfisch/servo,sadmansk/servo,mbrubeck/servo,SimonSapin/servo,szeged/servo,szeged/servo,sadmansk/servo,ConnorGBrewster/servo,saneyuki/servo,CJ8664/servo,splav/servo,sadmansk/servo,pyfisch/servo,eddyb/servo,upsuper/servo,mattnenterprise/servo,dsandeephegde/servo,mattnenterprise/servo,splav/servo,CJ8664/servo,emilio/servo,avadacatavra/servo,mattnenterprise/servo,fiji-flo/servo,emilio/servo,paulrouget/servo,notriddle/servo,mbrubeck/servo,splav/servo,rnestler/servo,mbrubeck/servo,DominoTree/servo,canaltinova/servo,mattnenterprise/servo,upsuper/servo,saneyuki/servo,mattnenterprise/servo,larsbergstrom/servo,peterjoel/servo,emilio/servo,larsbergstrom/servo,mbrubeck/servo,CJ8664/servo,dati91/servo,sadmansk/servo,splav/servo,jimberlage/servo,splav/servo,saneyuki/servo,notriddle/servo,paulrouget/servo,notriddle/servo,KiChjang/servo,szeged/servo,avadacatavra/servo,peterjoel/servo,DominoTree/servo,nnethercote/servo,nnethercote/servo,eddyb/servo,pyfisch/servo,larsbergstrom/servo,paulrouget/servo,larsbergstrom/servo,thiagopnts/servo,DominoTree/servo,saneyuki/servo,notriddle/servo,thiagopnts/servo,CJ8664/servo,SimonSapin/servo,anthgur/servo,saneyuki/servo,jimberlage/servo,sadmansk/servo,DominoTree/servo,eddyb/servo,nnethercote/servo,dsandeephegde/servo,szeged/servo,ConnorGBrewster/servo,cbrewster/servo,nnethercote/servo,saneyuki/servo,canaltinova/servo,mattnenterprise/servo,ConnorGBrewster/servo,thiagopnts/servo,mattnenterprise/servo,fiji-flo/servo,canaltinova/servo,emilio/servo,rnestler/servo,peterjoel/servo,rnestler/servo,emilio/servo,rnestler/servo,SimonSapin/servo,larsbergstrom/servo,nnethercote/servo,anthgur/servo,dsandeephegde/servo,ConnorGBrewster/servo,cbrewster/servo,avadacatavra/servo,peterjoel/servo,emilio/servo,notriddle/servo,szeged/servo,rnestler/servo,rnestler/servo,szeged/servo,paulrouget/servo,larsbergstrom/servo,pyfisch/servo,canaltinova/servo,thiagopnts/servo,thiagopnts/servo,jimberlage/servo,SimonSapin/servo,jimberlage/servo,cbrewster/servo,anthgur/servo,nnethercote/servo,KiChjang/servo,DominoTree/servo,jimberlage/servo,DominoTree/servo,SimonSapin/servo,emilio/servo,DominoTree/servo,cbrewster/servo,ConnorGBrewster/servo,emilio/servo,sadmansk/servo,anthgur/servo,anthgur/servo,dati91/servo,splav/servo,paulrouget/servo,dati91/servo,KiChjang/servo,dsandeephegde/servo,CJ8664/servo,jimberlage/servo,KiChjang/servo,dati91/servo,cbrewster/servo,szeged/servo,upsuper/servo,thiagopnts/servo,jimberlage/servo,ConnorGBrewster/servo,pyfisch/servo,pyfisch/servo,dsandeephegde/servo,mbrubeck/servo,CJ8664/servo,rnestler/servo,thiagopnts/servo,peterjoel/servo,avadacatavra/servo,nnethercote/servo,notriddle/servo,dati91/servo,larsbergstrom/servo,peterjoel/servo,saneyuki/servo,eddyb/servo,notriddle/servo,splav/servo,nnethercote/servo,KiChjang/servo,paulrouget/servo,jimberlage/servo,larsbergstrom/servo,szeged/servo,upsuper/servo,dati91/servo,dati91/servo,SimonSapin/servo,fiji-flo/servo,avadacatavra/servo,KiChjang/servo,mattnenterprise/servo,paulrouget/servo,notriddle/servo,nnethercote/servo,DominoTree/servo,DominoTree/servo,splav/servo,saneyuki/servo,fiji-flo/servo,fiji-flo/servo,avadacatavra/servo,cbrewster/servo,dsandeephegde/servo,pyfisch/servo,KiChjang/servo,mbrubeck/servo,DominoTree/servo,jimberlage/servo,dati91/servo,KiChjang/servo,fiji-flo/servo,szeged/servo,paulrouget/servo,paulrouget/servo,ConnorGBrewster/servo,paulrouget/servo,canaltinova/servo,peterjoel/servo,peterjoel/servo