[javascript mode] Recognize TypeScript typeof in type position
[javascript mode] Recognize TypeScript typeof in type position

Closes #5275

namin/CodeMirror,nightwing/CodeMirror,wingify/CodeMirror,namin/CodeMirror,notepadqq/CodeMirror,SidPresse/CodeMirror,hackmdio/CodeMirror,SidPresse/CodeMirror,dperetti/CodeMirror,codio/CodeMirror,pabloferz/CodeMirror,thomasjm/CodeMirror,codio/CodeMirror,mtaran-google/CodeMirror,pabloferz/CodeMirror,mtaran-google/CodeMirror,hackmdio/CodeMirror,jkaplon/CodeMirror,SidPresse/CodeMirror,mtaran-google/CodeMirror,nightwing/CodeMirror,thomasjm/CodeMirror,hackmdio/CodeMirror,wingify/CodeMirror,namin/CodeMirror,thomasjm/CodeMirror,dperetti/CodeMirror,notepadqq/CodeMirror,nightwing/CodeMirror,notepadqq/CodeMirror,jkaplon/CodeMirror,wingify/CodeMirror,codio/CodeMirror,dperetti/CodeMirror,jkaplon/CodeMirror,pabloferz/CodeMirror