Add a gecko_ffi_name property on longhands for the cases where Gecko has a weird property name.
Add a gecko_ffi_name property on longhands for the cases where Gecko has a weird property name.

Long-term it'd be better to just rename the stuff in Gecko, but this is more expedient for now.

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