fix vm_test

R=nweiz@google.com

Review URL: https://codereview.chromium.org//1654063003 .

pkgs/stack_trace/pubspec.yaml

diff --git a/pkgs/stack_trace/pubspec.yaml b/pkgs/stack_trace/pubspec.yaml
index e0fdbb9..1c180cf 100644
--- a/pkgs/stack_trace/pubspec.yaml
+++ b/pkgs/stack_trace/pubspec.yaml
@@ -7,7 +7,7 @@
 #
 # When the major version is upgraded, you *must* update that version constraint
 # in pub to stay in sync with this.
-version: 1.6.1
+version: 1.6.2-dev
 author: "Dart Team <misc@dartlang.org>"
 homepage: http://github.com/dart-lang/stack_trace
 description: >

pkgs/stack_trace/test/vm_test.dart

diff --git a/pkgs/stack_trace/test/vm_test.dart b/pkgs/stack_trace/test/vm_test.dart
index f0967b5..1b53458 100644
--- a/pkgs/stack_trace/test/vm_test.dart
+++ b/pkgs/stack_trace/test/vm_test.dart
@@ -12,6 +12,12 @@
 import 'package:stack_trace/stack_trace.dart';
 import 'package:test/test.dart';
 
+// The name of this (trivial) function is verified as part of the test
+String getStackTraceString() => StackTrace.current.toString();
+
+// The name of this (trivial) function is verified as part of the test
+StackTrace getStackTraceObject() => StackTrace.current;
+
 Frame getCaller([int level]) {
   if (level == null) return new Frame.caller();
   return new Frame.caller(level);
@@ -26,7 +32,7 @@
 void main() {
   group('Trace', () {
     test('.parse parses a real stack trace correctly', () {
-      var string = StackTrace.current.toString();
+      var string = getStackTraceString();
       var trace = new Trace.parse(string);
       expect(path.url.basename(trace.frames.first.uri.path),
           equals('vm_test.dart'));
@@ -34,7 +40,7 @@
     });
 
     test('converts from a native stack trace correctly', () {
-      var trace = new Trace.from(StackTrace.current);
+      var trace = new Trace.from(getStackTraceObject());
       expect(path.url.basename(trace.frames.first.uri.path),
           equals('vm_test.dart'));
       expect(trace.frames.first.member, equals('getStackTraceObject'));