Remove javascript generator from horizontal playground. Re GH-304
Remove javascript generator from horizontal playground. Re GH-304

LLK/scratch-blocks,LLK/scratch-blocks,gengshenghong/scratch-blocks,griffpatch/scratch-blocks,griffpatch/scratch-blocks,gengshenghong/scratch-blocks,sclements/scratch-blocks,LLK/scratch-blocks,sclements/scratch-blocks,griffpatch/scratch-blocks,griffpatch/scratch-blocks,griffpatch/scratch-blocks,sclements/scratch-blocks,LLK/scratch-blocks,sclements/scratch-blocks,LLK/scratch-blocks,gengshenghong/scratch-blocks,sclements/scratch-blocks,gengshenghong/scratch-blocks,gengshenghong/scratch-blocks