Fix coroutine generation in case of empty lambda

'handleResult' should be called in such case too

compiler/testData/codegen/box/coroutines/handleResultCallEmptyBody.kt

@@ -0,0 +1,20 @@
+class Controller {
+    var ok = false
+
+    operator fun handleResult(u: Unit, v: Continuation<Nothing>) {
+        ok = true
+    }
+}
+
+fun builder(coroutine c: Controller.() -> Continuation<Unit>): String {
+    val controller = Controller()
+    c(controller).resume(Unit)
+    if (!controller.ok) throw java.lang.RuntimeException("Was not called")
+    return "OK"
+}
+
+fun unitFun() {}
+
+fun box(): String {
+    return builder {}
+}