Process default arguments in array convention calls

#KT-16520 Fixed

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

@@ -0,0 +1,34 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+var inc: String = ""
+
+class X {
+    var result: String = "fail"
+
+    operator fun get(name: String, type: Int = 100) = name + type
+
+    operator fun set(name: String, defaultParam: String = "_default_", value: String) {
+        result = name + defaultParam + value;
+    }
+}
+
+class Y {
+    var result: String = "fail"
+
+    operator fun get(name: String, type: String = "_default_", type2: Int = 2) = name + type + type2
+
+    operator fun set(name: String, defaultParam: String = "_default_in_setter_", value: String) {
+        result = name + defaultParam + value;
+    }
+}
+
+fun box(): String {
+    var x = X()
+    x["index"] += "OK"
+    if (x.result != "index_default_index100OK") return "fail 1: ${x.result}"
+
+    var y = Y()
+    y["index"] += "OK"
+    if (y.result != "index_default_in_setter_index_default_2OK") return "fail 2: ${y.result}"
+
+    return "OK"
+}