K1/K2: add test for streams situation from intellij

compiler/testData/diagnostics/testsWithStdLib/streams/wrongNullability.fir.kt

@@ -0,0 +1,24 @@
+// FULL_JDK
+// JVM_TARGET: 1.8
+
+import java.util.function.IntPredicate
+import java.util.stream.Stream
+import kotlin.streams.toList
+
+class IntLongPair(val i: Int, val l: Long)
+
+interface Process {
+    fun pid(): Int
+
+    fun totalCpuDuration(): Long?
+}
+
+fun run(filter: IntPredicate, allProcesses: Stream<Process>): List<IntLongPair> {
+    return allProcesses.filter {
+        filter.test(it.pid())
+    }.map<IntLongPair?> {
+        val duration = it.totalCpuDuration()
+        if (duration != null) IntLongPair(it.pid(), duration)
+        else null
+    }.toList()
+}