Initial UI for Metrics in Observatory

runtime/bin/vmservice/observatory/test/metrics_test.dart

Index: runtime/bin/vmservice/observatory/test/metrics_test.dart
diff --git a/runtime/bin/vmservice/observatory/test/metrics_test.dart b/runtime/bin/vmservice/observatory/test/metrics_test.dart
index 92a5d470843265f484defbea1a774cd383ab8382..8ea13a8d9ab428be360e46aeeab80158b18a864f 100644
--- a/runtime/bin/vmservice/observatory/test/metrics_test.dart
+++ b/runtime/bin/vmservice/observatory/test/metrics_test.dart
@@ -23,14 +23,14 @@ var tests = [
     expect(members, isList);
     expect(members.length, equals(1));
     var counter = members[0];
-    expect(counter['name'], equals('a.b.c'));
-    expect(counter['value'], equals(1234.5));
+    expect(counter.name, equals('a.b.c'));
+    expect(counter.value, equals(1234.5));
 }),
 
 (Isolate isolate) =>
-  isolate.get('metrics/a.b.c').then((ServiceMap counter) {
-    expect(counter['name'], equals('a.b.c'));
-    expect(counter['value'], equals(1234.5));
+  isolate.get('metrics/a.b.c').then((ServiceMetric counter) {
+    expect(counter.name, equals('a.b.c'));
+    expect(counter.value, equals(1234.5));
 }),
 
 (Isolate isolate) =>