Fixed KT-3807 Wrong completion for class/trait with extesion function

#KT-3807 Fixed

idea/testData/completion/basic/common/extensions/WrongExplicitReceiver.kt

@@ -0,0 +1,10 @@
+class Foo {
+    fun Int.bar() = this
+}
+
+fun main(args: Array<String>) {
+    val v = Foo()
+    v.<caret>
+}
+
+// ABSENT: bar