KT-7472 function of anonymous class is never used

#KT-7472 fixed

idea/testData/findUsages/kotlin/findFunctionUsages/objectExpressionDeepMember.0.kt

@@ -0,0 +1,15 @@
+// PSI_ELEMENT: org.jetbrains.kotlin.psi.JetProperty
+// OPTIONS: usages
+package anonymousUnused
+
+fun main(args: Array<String>) {
+    val a = object {
+        val b = object {
+            val c = object {
+                val <caret>d = 5
+            }
+        }
+    }
+
+    a.b.c.d
+}