[JS IR] Add stdlib regression tests

js/js.translator/testData/box/regression/stdlibTestSnippets/throwable.kt

@@ -0,0 +1,51 @@
+// EXPECTED_REACHABLE_NODES: 1279
+// Snippet from stdlib test test.exceptions.ExceptionTest
+
+private val cause = Exception("cause")
+
+fun assertSame(x: Any?, y: Any?) {
+    if (x !== y) {
+        error("Assertion failed")
+    }
+}
+
+private fun <T : Throwable> testCreateException(
+    noarg: () -> T,
+    fromMessage: (String?) -> T,
+    fromCause: ((Throwable?) -> T)? = null,
+    fromMessageCause: ((String?, Throwable?) -> T)? = null
+) {
+    noarg().let { e ->
+        assertEquals(null, e.message)
+        assertEquals(null, e.cause)
+    }
+
+    fromMessage("message").let { e ->
+        assertEquals("message", e.message)
+        assertEquals(null, e.cause)
+    }
+
+    fromMessage(null).let { e ->
+        assertTrue(e.message == null || e.message == "null")
+    }
+
+    fromMessageCause?.run {
+        invoke("message", cause).let { e ->
+            assertEquals("message", e.message)
+            assertSame(cause, e.cause)
+        }
+        invoke(null, null).let { e ->
+            assertEquals(null, e.message)
+            assertEquals(null, e.cause)
+        }
+    }
+
+    fromCause?.invoke(cause)?.let { e ->
+        assertSame(cause, e.cause)
+    }
+}
+
+fun box(): String {
+    testCreateException(::Throwable, ::Throwable, ::Throwable, ::Throwable)
+    return "OK"
+}