Add a VM page to the observatory.

tests/standalone/vmservice/isolate_echo_test.dart

Index: tests/standalone/vmservice/isolate_echo_test.dart
diff --git a/tests/standalone/vmservice/isolate_echo_test.dart b/tests/standalone/vmservice/isolate_echo_test.dart
index 2f311d293a3d5c0c7562aa440ebb96ebd7b702da..cf0f325f3a299dbd2c5c3042d19f119e363ab7e1 100644
--- a/tests/standalone/vmservice/isolate_echo_test.dart
+++ b/tests/standalone/vmservice/isolate_echo_test.dart
@@ -33,12 +33,12 @@ class EchoRequestTest extends VmServiceRequestHelper {
   }
 }
 
-class IsolateListTest extends VmServiceRequestHelper {
-  IsolateListTest(port) : super('http://127.0.0.1:$port/isolates');
+class VMTest extends VmServiceRequestHelper {
+  VMTest(port) : super('http://127.0.0.1:$port/vm');
 
   String _isolateId;
   onRequestCompleted(Map reply) {
-    IsolateListTester tester = new IsolateListTester(reply);
+    VMTester tester = new VMTester(reply);
     tester.checkIsolateCount(1);
     _isolateId = tester.getIsolateId(0);
   }
@@ -48,7 +48,7 @@ class IsolateListTest extends VmServiceRequestHelper {
 main() {
   var process = new TestLauncher('isolate_echo_script.dart');
   process.launch().then((port) {
-    var test = new IsolateListTest(port);
+    var test = new VMTest(port);
     test.makeRequest().then((_) {
       var echoRequestTest = new EchoRequestTest(port, test._isolateId);
       echoRequestTest.makeRequest().then((_) {