Auto merge of #11299 - servo:GlutinCompositorProxy-Send, r=nox
Auto merge of #11299 - servo:GlutinCompositorProxy-Send, r=nox

Remove unsafe Send implementation for GlutinCompositorProxy.

Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data:
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy --faster` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

Either:
- [ ] There are tests for these changes OR
- [x] These changes do not require tests because _____

Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process.

Send is now implemented for glutin::WindowProxy.

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