Add "defer" attribute for script tags to html5_contract RELNOTES: Allow "defer" attribute to be set on script elements
Add "defer" attribute for script tags to html5_contract
RELNOTES: Allow "defer" attribute to be set on script elements

PiperOrigin-RevId: 342069073

google/closure-library,google/closure-library,google/closure-library,google/closure-library,google/closure-library