Chests: Revert inventory name

Revert the new 'default:game' inventory back to the old 'main' and use the
lbm to restore the contents of the chest.
Change the name of the conversion LBM to ensure it is run again on already
converted chests.

mods/default/nodes.lua

@@ -1773,10 +1773,10 @@ local function get_chest_formspec(pos)
 		default.gui_bg ..
 		default.gui_bg_img ..
 		default.gui_slots ..
-		"list[nodemeta:" .. spos .. ";default:chest;0,0.3;8,4;]" ..
+		"list[nodemeta:" .. spos .. ";main;0,0.3;8,4;]" ..
 		"list[current_player;main;0,4.85;8,1;]" ..
 		"list[current_player;main;0,6.08;8,3;8]" ..
-		"listring[nodemeta:" .. spos .. ";default:chest]" ..
+		"listring[nodemeta:" .. spos .. ";main]" ..
 		"listring[current_player;main]" ..
 		default.get_hotbar_bg(0,4.85)
 	return formspec
@@ -1842,7 +1842,7 @@ function default.register_chest(name, d)
 			meta:set_string("infotext", "Locked Chest")
 			meta:set_string("owner", "")
 			local inv = meta:get_inventory()
-			inv:set_size("default:chest", 8*4)
+			inv:set_size("main", 8*4)
 		end
 		def.after_place_node = function(pos, placer)
 			local meta = minetest.get_meta(pos)
@@ -1853,7 +1853,7 @@ function default.register_chest(name, d)
 		def.can_dig = function(pos,player)
 			local meta = minetest.get_meta(pos);
 			local inv = meta:get_inventory()
-			return inv:is_empty("default:chest") and
+			return inv:is_empty("main") and
 					default.can_interact_with_node(player, pos)
 		end
 		def.allow_metadata_inventory_move = function(pos, from_list, from_index,
@@ -1939,12 +1939,12 @@ function default.register_chest(name, d)
 			local meta = minetest.get_meta(pos)
 			meta:set_string("infotext", "Chest")
 			local inv = meta:get_inventory()
-			inv:set_size("default:chest", 8*4)
+			inv:set_size("main", 8*4)
 		end
 		def.can_dig = function(pos,player)
 			local meta = minetest.get_meta(pos);
 			local inv = meta:get_inventory()
-			return inv:is_empty("default:chest")
+			return inv:is_empty("main")
 		end
 		def.on_rightclick = function(pos, node, clicker)
 			minetest.sound_play(def.sound_open, {gain = 0.3, pos = pos,
@@ -2007,16 +2007,18 @@ function default.register_chest(name, d)
 	-- convert old chests to this new variant
 	minetest.register_lbm({
 		label = "update chests to opening chests",
-		name = "default:upgrade_" .. name,
+		name = "default:upgrade_" .. name .. "_v2",
 		nodenames = {"default:" .. name},
 		action = function(pos, node)
 			local meta = minetest.get_meta(pos)
 			meta:set_string("formspec", nil)
 			local inv = meta:get_inventory()
-			local list = inv:get_list("main")
-			inv:set_list("main", nil)
-			inv:set_size("default:chest", 8*4)
-			inv:set_list("default:chest", list)
+			local list = inv:get_list("default:chest")
+			if list then
+				inv:set_size("main", 8*4)
+				inv:set_list("main", list)
+				inv:set_list("default:chest", nil)
+			end
 		end
 	})
 end