add missing deepAssign()

src/arcologyBuilding/base.js

@@ -254,9 +254,7 @@ App.Arcology.Building = class {
 		// `JSON.reviveWrapper()` call will trigger out of control recursion in
 		// the serializer, so we must pass it a clone of our own data instead.
 		const ownData = {};
-		Object.keys(this).forEach(function(pn) {
-			ownData[pn] = clone(this[pn]);
-		}, this);
+		deepAssign(ownData, this);
 		return JSON.reviveWrapper('(new App.Arcology.Building())._init($ReviveData$)', ownData);
 	}
 };