The tag compound holds item data that is not the root id, Damage, Count, or Slot tags. The Damage tag will state the color of the glass.
You should also not be using the TileID tag because it is deprecated. Use Block instead, which holds the string name of the block. The Time tag is an integer, not a double, so you cannot use decimals.
/summon minecraft:falling_block ~1 ~ ~ {Block:"minecraft:chest",Time:1,TileEntityData:{Items:[{id:"minecraft:stained_glass",Damage:4,Slot:1,Count:1,tag:{CanPlaceOn:["minecraft:iron_block"]}}]}}