Custom Spawners dont work via Set Block Command

I have found that via set block command that custom spawners do not work. This issue can be replicated by placing a command block and I specifically used "/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace

{EntityId:Zombie}

" without quotations of course to see if it would spawn via set block command and it only spawned a pig spawner instead of a zombie spawner. Video link included to show bug https://www.youtube.com/watch?v=9vvB9FDtQkQ&feature=youtu.be