[FE] Do not change original semantics in LabelResolver

compiler/testData/diagnostics/tests/extensions/contextReceivers/noLabelsByClassName.kt

@@ -0,0 +1,27 @@
+fun Int.f() {
+    this<!UNRESOLVED_REFERENCE!>@Int<!>
+}
+
+var Int.p: Int
+    get() {
+        this<!UNRESOLVED_REFERENCE!>@Int<!>
+        return<!UNRESOLVED_REFERENCE!>@p<!> 42
+    }
+    set(value) {
+        this<!UNRESOLVED_REFERENCE!>@Int<!>
+    }
+
+class X {
+    var Int.p: Int
+        get() {
+            this<!UNRESOLVED_REFERENCE!>@Int<!>
+            return<!UNRESOLVED_REFERENCE!>@p<!> 42
+        }
+        set(value) {
+            this<!UNRESOLVED_REFERENCE!>@Int<!>
+        }
+
+    fun Int.f() {
+        this<!UNRESOLVED_REFERENCE!>@Int<!>
+    }
+}