Minor. Add more tests

compiler/testData/codegen/box/inlineClasses/elvisWithInlineClassAndNullConstantGeneric.kt

@@ -0,0 +1,19 @@
+// WITH_STDLIB
+// WORKS_WHEN_VALUE_CLASS
+// LANGUAGE: +ValueClasses, +GenericInlineClassParameter
+
+OPTIONAL_JVM_INLINE_ANNOTATION
+value class UInt<T: Int>(private val data: T) {
+    fun result(): String = if (data == 1) "OK" else "fail"
+}
+
+fun f(): UInt<Int> {
+    val unull = UInt(1) ?: null
+    return nonNull(unull)
+}
+
+fun <T: Int> nonNull(u: UInt<T>?) = u!!
+
+fun box(): String {
+    return f().result()
+}