Fix an awful bug in LRUCache::touch().
Fix an awful bug in LRUCache::touch().

MozReview-Commit-ID: 3l7L0MfdOxh

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