Enables clean VM shutdown.

runtime/vm/metrics_test.cc

Index: runtime/vm/metrics_test.cc
diff --git a/runtime/vm/metrics_test.cc b/runtime/vm/metrics_test.cc
index faf425bffd3d3ae85563d7a704b1dec85550823e..a89484c6d663c1e2dcda75713fd50a7e99f81aa1 100644
--- a/runtime/vm/metrics_test.cc
+++ b/runtime/vm/metrics_test.cc
@@ -28,6 +28,8 @@ UNIT_TEST_CASE(Metric_Simple) {
   EXPECT_EQ(1, metric.value());
   metric.set_value(44);
   EXPECT_EQ(44, metric.value());
+
+  Dart::ShutdownIsolate();
 }
 
 class MyMetric : public Metric {
@@ -48,24 +50,27 @@ UNIT_TEST_CASE(Metric_OnDemand) {
   vm_flags.CopyTo(&api_flags);
   Isolate* isolate = Isolate::Init(NULL, api_flags);
   EXPECT_EQ(isolate, Isolate::Current());
-  StackZone zone(isolate);
-  HANDLESCOPE(isolate);
-  MyMetric metric;
+  {
+    StackZone zone(isolate);
+    HANDLESCOPE(isolate);
+    MyMetric metric;
 
-  metric.Init(Isolate::Current(), "a.b.c", "foobar", Metric::kByte);
-  // value is still the default value.
-  EXPECT_EQ(0, metric.value());
-  // Call LeakyValue to confirm that Value returns constant 99.
-  EXPECT_EQ(99, metric.LeakyValue());
+    metric.Init(Isolate::Current(), "a.b.c", "foobar", Metric::kByte);
+    // value is still the default value.
+    EXPECT_EQ(0, metric.value());
+    // Call LeakyValue to confirm that Value returns constant 99.
+    EXPECT_EQ(99, metric.LeakyValue());
 
-  // Serialize to JSON.
-  JSONStream js;
-  metric.PrintJSON(&js);
-  const char* json = js.ToCString();
-  EXPECT_STREQ("{\"type\":\"Counter\",\"name\":\"a.b.c\",\"description\":"
-               "\"foobar\",\"unit\":\"byte\","
-               "\"fixedId\":true,\"id\":\"metrics\\/native\\/a.b.c\""
-               ",\"value\":99.000000}", json);
+    // Serialize to JSON.
+    JSONStream js;
+    metric.PrintJSON(&js);
+    const char* json = js.ToCString();
+    EXPECT_STREQ("{\"type\":\"Counter\",\"name\":\"a.b.c\",\"description\":"
+                 "\"foobar\",\"unit\":\"byte\","
+                 "\"fixedId\":true,\"id\":\"metrics\\/native\\/a.b.c\""
+                 ",\"value\":99.000000}", json);
+  }
+  Dart::ShutdownIsolate();
 }
 
 }  // namespace dart