Auto merge of #14366 - heycam:variables, r=Manishearth
Auto merge of #14366 - heycam:variables, r=Manishearth

move Servo_GetStyleVariables definition from the Gecko side

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This is the Servo-side part of https://bugzilla.mozilla.org/show_bug.cgi?id=1319982 which has already been reviewed by @Manishearth there.

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