Code clean, small refactorings and tests

#KT-8987 Fixed

compiler/testData/codegen/bytecodeText/argumentOrder/argumentReorderWithDefault.kt

@@ -0,0 +1,13 @@
+class A {
+    fun test(x: String? = "x", a: String?, b: String?, y: String? = "y") {
+
+    }
+
+    fun box(): String {
+        test(b = "K", a = "O")
+        return "OK"
+    }
+}
+// Test argument reordering when call site argument order differs from declaration one
+// 12 LOAD
+// 5 STORE