Fix for KT-9140: Default parameters are passed as nulls when using indexing [ ] invocation

#KT-9140 Fixed

compiler/testData/codegen/box/defaultArguments/convention/kt9140.kt

@@ -0,0 +1,11 @@
+class X {
+    operator fun get(name: String, type: String = "none") = name + type
+}
+
+fun box(): String {
+    if (X().get("a") != "anone") return "fail 1: ${X().get("a")}"
+
+    if (X()["a"] != "anone") return "fail 2: ${X()["a"]}"
+
+    return "OK"
+}