Run dartfmt on remaining unformated pkg packages

pkg/testing/lib/src/zone_helper.dart

 // Copyright (c) 2016, the Dart project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE.md file.
 
 /// Helper functions for running code in a Zone.
 library testing.zone_helper;
 
-import 'dart:async' show
-    Completer,
-    Future,
-    ZoneSpecification,
-    runZoned;
+import 'dart:async' show Completer, Future, ZoneSpecification, runZoned;
 
-import 'dart:io' show
-    exit,
-    stderr;
+import 'dart:io' show exit, stderr;
 
-import 'dart:isolate' show
-    Capability,
-    Isolate,
-    ReceivePort;
+import 'dart:isolate' show Capability, Isolate, ReceivePort;
 
-import 'log.dart' show
-    logUncaughtError;
+import 'log.dart' show logUncaughtError;
 
-Future runGuarded(
-    Future f(),
+Future runGuarded(Future f(),
     {void printLineOnStdout(line),
-     void handleLateError(error, StackTrace stackTrace)}) {
-
+    void handleLateError(error, StackTrace stackTrace)}) {
   var printWrapper;
   if (printLineOnStdout != null) {
     printWrapper = (_1, _2, _3, String line) {
       printLineOnStdout(line);
     };
   }
 
   Completer completer = new Completer();
 
   handleUncaughtError(error, StackTrace stackTrace) {
     logUncaughtError(error, stackTrace);
     if (!completer.isCompleted) {
       completer.completeError(error, stackTrace);
     } else if (handleLateError != null) {
       handleLateError(error, stackTrace);
     } else {
       String errorString = "error.toString() failed.";
       try {
         errorString = "$error";
       } catch (_) {
         // Ignored.
       }
-      stderr.write("$errorString\n" +
-          (stackTrace == null ? "" : "$stackTrace"));
+      stderr
+          .write("$errorString\n" + (stackTrace == null ? "" : "$stackTrace"));
       stderr.flush();
       exit(255);
     }
   }
 
   ZoneSpecification specification = new ZoneSpecification(print: printWrapper);
 
   ReceivePort errorPort = new ReceivePort();
   Future errorFuture = errorPort.listen((List errors) {
     Isolate.current.removeErrorListener(errorPort.sendPort);
     errorPort.close();
     var error = errors[0];
     var stackTrace = errors[1];
     if (stackTrace != null) {
       stackTrace = new StackTrace.fromString(stackTrace);
     }
     handleUncaughtError(error, stackTrace);
   }).asFuture();
 
   Isolate.current.setErrorsFatal(false);
   Isolate.current.addErrorListener(errorPort.sendPort);
   return acknowledgeControlMessages(Isolate.current).then((_) {
-    runZoned(
-        () => new Future(f).then(completer.complete),
-        zoneSpecification: specification,
-        onError: handleUncaughtError);
+    runZoned(() => new Future(f).then(completer.complete),
+        zoneSpecification: specification, onError: handleUncaughtError);
 
     return completer.future.whenComplete(() {
       errorPort.close();
       Isolate.current.removeErrorListener(errorPort.sendPort);
       return acknowledgeControlMessages(Isolate.current)
           .then((_) => errorFuture);
     });
   });
 }
 
 /// Ping [isolate] to ensure control messages have been delivered.  Control
 /// messages are things like [Isolate.addErrorListener] and
 /// [Isolate.addOnExitListener].
 Future acknowledgeControlMessages(Isolate isolate, {Capability resume}) {
   ReceivePort ping = new ReceivePort();
   Isolate.current.ping(ping.sendPort);
   if (resume == null) {
     return ping.first;
   } else {
     return ping.first.then((_) => isolate.resume(resume));
   }
 }