Avoid useless if‑else check during fallback type conversion

[ExE-Boss]

This makes it so that for fallback types (e.g. boolean and number), if it’s the last fallback type among overloads or in a union, then the conversion will no longer be duplicated in the if‑and‑else branches:

-} else if (typeof curArg === \\"boolean\\") {
-	{
-		let curArg = arguments[0];
-		curArg = conversions[\\"boolean\\"](curArg, {
-			context: \\"Failed to execute 'overloadsObjectOrBoolean' on 'NoUselessIfElse': parameter 1\\"
-		});
-		args.push(curArg);
-	}
 } else {
 	{
 		let curArg = arguments[0];
 		curArg = conversions[\\"boolean\\"](curArg, {
 			context: \\"Failed to execute 'overloadsObjectOrBoolean' on 'NoUselessIfElse': parameter 1\\"
 		});
 		args.push(curArg);
 	}
 }

Depends on:

• Avoid generating broken code when the object type is in a union #231

[TimothyGu]

I'd rather not do this, since it makes the code harder to maintain by diverging from the overload resolution algorithm in the spec.