Corresponds to whether the player has already seen the image for the following rooms:

Bit	Room ID	Room Name
00	05	The Great Valley
01	0F	At the Woodman's Hut
02	18	The Old Well
03	44	At the Base of a Volcano
04	3C	At the Witch's Hovel
05	11	A Burned out Farm
06	23	The Enchanted Wood
07	24	The Enchanted Wood

Bit	Room ID	Room Name
00	25	The Enchanted Wood
01	4C	The Dungeon
02	35	Marl's Gateway
03	46	The Cavern of Silence
04	N/A	N/A
05	N/A	N/A
06	N/A	N/A
07	N/A	N/A

Handler_DisplayRoom tests and sets the bit for the current room. The bit number is the room's place in E806.