[FIR-TEST] Add new testdata generated after changes in previous commit

compiler/testData/diagnostics/tests/nullabilityAndSmartCasts/kt30734.fir.kt

@@ -0,0 +1,16 @@
+// !DIAGNOSTICS: -UNUSED_VARIABLE
+// !WITH_NEW_INFERENCE
+// !LANGUAGE: +NewInference
+// Issue: KT-30734
+
+class Sample {
+    fun foo(): Boolean = true
+}
+
+fun test(ls: Sample?) {
+    val filter: () -> Boolean = if (ls == null) {
+        { false }
+    } else {
+        { ls.foo() } // OK in OI, error in NI
+    }
+}