Codegen for callable reference expressions

#KT-1183 In Progress

compiler/testData/codegen/box/callableReference/abstractClassMember.kt

@@ -0,0 +1,9 @@
+abstract class A {
+    abstract fun foo(): String
+}
+
+class B : A() {
+    override fun foo() = "OK"
+}
+
+fun box(): String = B().(A::foo)()