Implement spawnDomUri.

tests/html/dom_isolates_test.dart

Index: tests/html/dom_isolates_test.dart
diff --git a/tests/html/dom_isolates_test.dart b/tests/html/dom_isolates_test.dart
index 7ce1386c25aa2ef3d63fe9509a02c81375602c4b..39092bc965510bfb08cf4b8e31327a1e06676de4 100644
--- a/tests/html/dom_isolates_test.dart
+++ b/tests/html/dom_isolates_test.dart
@@ -36,15 +36,19 @@ main() {
   useHtmlConfiguration();
 
   test('Simple DOM isolate test', () {
-    spawnDomFunction(childDomIsolate).then((sendPort) {
-      expect(sendPort.call('check'), completion('${window.location}'));
-    });
+    spawnDomFunction(childDomIsolate).then(expectAsync1(
+        (sendPort) {
+            expect(sendPort.call('check'), completion('${window.location}'));
+        }
+    ));
   });
 
   test('Nested DOM isolates test', () {
-    spawnDomFunction(trampolineIsolate).then((sendPort) {
-      expect(sendPort.call('check'), completion('${window.location}'));
-    });
+    spawnDomFunction(trampolineIsolate).then(expectAsync1(
+        (sendPort) {
+            expect(sendPort.call('check'), completion('${window.location}'));
+        }
+    ));
   });
 
   test('Spawn DOM isolate from pure', () {
@@ -52,6 +56,14 @@ main() {
            completion('${window.location}'));
   });
 
+  test('Spawn DOM by uri', () {
+    spawnDomUri('dom_isolates_test.dart.child_isolate.dart').then(expectAsync1(
+        (sendPort) {
+            expect(sendPort.call('check'), completion('${window.location}'));
+        }
+    ));
+  });
+
   test('Not function', () {
       expect(() => spawnDomFunction(42), throws);
   });