Refactor groups to pipe them through to the runner.

lib/src/runner/load_suite.dart

Index: lib/src/runner/load_suite.dart
diff --git a/lib/src/runner/load_suite.dart b/lib/src/runner/load_suite.dart
index 0c1dabc5fa91afd3dae58b71e3d901b12b2272bb..04eb1cbf299ff5a49c34fb28fb0e5836e1199484 100644
--- a/lib/src/runner/load_suite.dart
+++ b/lib/src/runner/load_suite.dart
@@ -11,6 +11,7 @@ import 'package:stack_trace/stack_trace.dart';
 import '../../test.dart';
 import '../backend/invoker.dart';
 import '../backend/metadata.dart';
+import '../backend/test.dart';
 import '../backend/test_platform.dart';
 import '../utils.dart';
 import 'load_exception.dart';
@@ -39,6 +40,12 @@ class LoadSuite extends RunnerSuite {
   /// example if an error occurred while loading it).
   final Future<RunnerSuite> suite;
 
+  /// Returns the test that loads the suite.
+  ///
+  /// Load suites are guaranteed to only contain one test. This is a utility
+  /// method for accessing it directly.
+  Test get test => entries.single as Test;
+
   /// Creates a load suite named [name] on [platform].
   ///
   /// [body] may return either a [RunnerSuite] or a [Future] that completes to a
@@ -108,7 +115,7 @@ class LoadSuite extends RunnerSuite {
 
   /// A constructor used by [changeSuite].
   LoadSuite._changeSuite(LoadSuite old, Future<RunnerSuite> this.suite)
-      : super(const VMEnvironment(), old.tests, platform: old.platform);
+      : super(const VMEnvironment(), old.entries, platform: old.platform);
 
   /// Creates a new [LoadSuite] that's identical to this one, but that
   /// transforms [suite] once it's loaded.
@@ -126,7 +133,7 @@ class LoadSuite extends RunnerSuite {
   /// Rather than emitting errors through a [LiveTest], this just pipes them
   /// through the return value.
   Future<RunnerSuite> getSuite() async {
-    var liveTest = await tests.single.load(this);
+    var liveTest = await test.load(this);
     liveTest.onPrint.listen(print);
     await liveTest.run();