Auto merge of #13478 - mmatyas:arm_gles3, r=jdm
Auto merge of #13478 - mmatyas:arm_gles3, r=jdm

Use GL ES3 on ARM devices

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This makes WebRender work on ARM devices; see servo/webrender#408.

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<!-- 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] `PKG_CONFIG_ALLOW_CROSS=1 PKG_CONFIG_PATH=/usr/lib/arm-linux-gnueabihf/pkgconfig HARFBUZZ_NO_PKG_CONFIG=1 EXPAT_NO_PKG_CONFIG=1 FREETYPE2_NO_PKG_CONFIG=1 FONTCONFIG_NO_PKG_CONFIG=1 CC=arm-linux-gnueabihf-gcc CXX=arm-linux-gnueabihf-g++ ./mach build --dev --target=arm-unknown-linux-gnueabihf` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #10310.

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