Auto merge of #9813 - glennw:iframe-sizing, r=pcwalton
Auto merge of #9813 - glennw:iframe-sizing, r=pcwalton

With WebRender, only send resize events when window size is valid.

Fixes WR 112.

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