Add SerializedScriptValueTest.

client/tests/client/dom/utils.dart

Index: client/tests/client/dom/utils.dart
diff --git a/client/tests/client/dom/utils.dart b/client/tests/client/dom/utils.dart
new file mode 100644
index 0000000000000000000000000000000000000000..7072f0c71473b3ade392429d8f3cd03cad0eb487
--- /dev/null
+++ b/client/tests/client/dom/utils.dart
@@ -0,0 +1,61 @@
+#library('TestUtils');
+
+/**
+ * Verifies that [actual] has the same graph structure as [expected].
+ * Detects cycles and DAG structure in Maps and Lists.
+ */
+verifyGraph(expected, actual) {
+  var eItems = [];
+  var aItems = [];
+
+  message(path, reason) => path == ''
+      ? reason
+      : reason == null ? "path: $path" : "path: $path, $reason";
+
+  walk(path, expected, actual) {
+    if (expected is String || expected is num || expected == null) {
+      Expect.equals(expected, actual, message(path, 'not equal'));
+      return;
+    }
+
+    // Cycle or DAG?
+    for (int i = 0; i < eItems.length; i++) {
+      if (expected === eItems[i]) {
+        Expect.identical(aItems[i], actual, message(path, 'back or side edge'));
+        return;
+      }
+    }
+    eItems.add(expected);
+    aItems.add(actual);
+
+    if (expected is List) {
+      Expect.isTrue(actual is List, message(path, '$actual is List'));
+      Expect.equals(expected.length, actual.length,
+                    message(path, 'different list lengths'));
+      for (var i = 0; i < expected.length; i++) {
+        walk('$path[$i]', expected[i], actual[i]);
+      }
+      return;
+    }
+
+    if (expected is Map) {
+      Expect.isTrue(actual is Map, message(path, '$actual is Map'));
+      for (var key in expected.getKeys()) {
+        if (!actual.containsKey(key)) {
+          Expect.fail(message(path, 'missing key "$key"'));
+        }
+        walk('$path["$key"]',  expected[key], actual[key]);
+      }
+      for (var key in actual.getKeys()) {
+        if (!expected.containsKey(key)) {
+          Expect.fail(message(path, 'extra key "$key"'));
+        }
+      }
+      return;
+    }
+
+    Expect.fail('Unhandled type: $expected');
+  }
+
+  walk('', expected, actual);
+}