[wasm] Also test structured stack trace

test/intl/assert.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 91 matching lines @@
  * Throws if two variables have different types or values.
  */
 function assertEquals(expected, found, user_message = '') {
   if (!deepEquals(expected, found)) {
     fail(expected, found, user_message);
   }
 }
 
 
 /**
+ * Throws if value does not contain sub.
+ */
+function assertContains(value, sub, user_message = '') {
+  if (value == null ? (sub != null) : value.indexOf(sub) == -1) {
+    fail("contains '" + String(sub) + "'", value, user_message);
+  }
+}
+
+
+/**
  * Throws if value is false.
  */
 function assertTrue(value, user_message = '') {
   assertEquals(true, value, user_message);
 }
 
 
 /**
  * Throws if value is true.
  */
@@ skipping 52 matching lines @@
     var actualTypeName = null;
     var actualConstructor = Object.prototypeOf(obj).constructor;
     if (typeof actualConstructor == "function") {
       actualTypeName = actualConstructor.name || String(actualConstructor);
     }
     throw new Error('Object <' + obj + '> is not an instance of <' +
          (type.name || type) + '>' +
          (actualTypeName ? ' but of < ' + actualTypeName + '>' : ''));
   }
 }