JS: move expressions test to box tests

js/js.translator/testData/box/expression/when/whenAsExpressionWithThrow.kt

@@ -0,0 +1,22 @@
+package foo
+
+fun box(): String {
+
+    try {
+        (when (1) {
+            3 -> {
+                3
+            }
+            1 -> {
+                throw Exception()
+            }
+            else -> {
+                return "fail1"
+            }
+        })
+    } catch (e: Exception) {
+        return "OK"
+    }
+
+    return "fail2"
+}