Remove all deprecated stuff in the IR.
Remove all deprecated stuff in the IR.

gzm0/scala-js,nicolasstucki/scala-js,nicolasstucki/scala-js,SebsLittleHelpers/scala-js,sjrd/scala-js,scala-js/scala-js,scala-js/scala-js,scala-js/scala-js,sjrd/scala-js,gzm0/scala-js,sjrd/scala-js,SebsLittleHelpers/scala-js