Minor. Add regression test

#KT-52561 Fixed

compiler/testData/codegen/box/coroutines/kt52561.kt

@@ -0,0 +1,31 @@
+// WITH_STDLIB
+// WITH_COROUTINES
+import helpers.*
+import kotlin.coroutines.*
+import kotlin.coroutines.intrinsics.*
+
+fun someCondition() = true
+
+suspend fun suspendHere() = suspendCoroutineUninterceptedOrReturn {
+    it.resume(Unit)
+    COROUTINE_SUSPENDED
+}
+
+fun expectString(x: String?) {
+    if (x != "TEST") error("FAIL: $x")
+}
+
+suspend fun test(block: (String) -> Unit) {
+    val string: String? = "TEST".takeIf { true }
+    check(string != null) // smartcast from String? to String
+    expectString(string)
+    suspendHere()
+    expectString(string)
+    block(string)
+}
+
+
+fun box(): String {
+    suspend { test {} }.startCoroutine(EmptyContinuation)
+    return "OK"
+}