Run dartfmt on all files under runtime.

runtime/observatory/tests/service/weak_properties_test.dart

Index: runtime/observatory/tests/service/weak_properties_test.dart
diff --git a/runtime/observatory/tests/service/weak_properties_test.dart b/runtime/observatory/tests/service/weak_properties_test.dart
index 02f4d31721945afaffa9a01ab6f3bcddc2cb4f87..a7705e8693757d84572647dfeb762a43c53aa6d6 100644
--- a/runtime/observatory/tests/service/weak_properties_test.dart
+++ b/runtime/observatory/tests/service/weak_properties_test.dart
@@ -10,8 +10,9 @@ import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
 import 'test_helper.dart';
 
-class Foo { }
-class Bar { }
+class Foo {}
+
+class Bar {}
 
 var expando;
 var key;
@@ -27,13 +28,14 @@ void script() {
   InstanceMirror expandoMirror = reflect(expando);
   LibraryMirror libcore = expandoMirror.type.owner;
 
-  var entries = expandoMirror.getField(MirrorSystem.getSymbol('_data', libcore)).reflectee;
+  var entries = expandoMirror
+      .getField(MirrorSystem.getSymbol('_data', libcore))
+      .reflectee;
   weak_property = entries.singleWhere((e) => e != null);
   print(weak_property);
 }
 
 var tests = [
-
   (Isolate isolate) async {
     var lib = await isolate.rootLibrary.load();
     Field keyField = lib.variables.singleWhere((v) => v.name == 'key');
@@ -42,7 +44,8 @@ var tests = [
     Field valueField = lib.variables.singleWhere((v) => v.name == 'value');
     await valueField.load();
     Instance value = valueField.staticValue;
-    Field propField = lib.variables.singleWhere((v) => v.name == 'weak_property');
+    Field propField =
+        lib.variables.singleWhere((v) => v.name == 'weak_property');
     await propField.load();
     Instance prop = propField.staticValue;
 
@@ -60,7 +63,6 @@ var tests = [
     expect(loadedProp.value, isNotNull);
     expect(loadedProp.value.clazz, equals(value.clazz));
   },
-
 ];
 
 main(args) => runIsolateTests(args, tests, testeeBefore: script);