set explicit receiver kind properly for calls

compiler/testData/resolvedCalls/invoke/thisObjectAsReceiverForInvoke.kt

@@ -0,0 +1,12 @@
+// !CALL: invoke
+// !EXPLICIT_RECEIVER_KIND: THIS_OBJECT
+// !THIS_OBJECT: f
+// !RECEIVER_ARGUMENT: NO_RECEIVER
+
+class Foo {
+    fun invoke() {}
+}
+
+fun bar(f: Foo) {
+    f()
+}