Tests for KT-3646: Wrong this in closure for extension function in constructor

#KT-3646 Obsolete

compiler/testData/codegen/box/extensionFunctions/kt3646.kt

@@ -0,0 +1,11 @@
+fun test(cl: Int.() -> Int):Int = 11.cl()
+
+class Foo {
+    val a = test { this }
+}
+
+fun box(): String {
+    if (Foo().a != 11) return "fail"
+
+    return "OK"
+}