Normalize handling of the package root in the runner.

lib/src/executable.dart

 // Copyright (c) 2015, 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 file.
 
 // TODO(nweiz): This is under lib so that it can be used by the unittest dummy
 // package. Once that package is no longer being updated, move this back into
 // bin.
 library test.executable;
 
 import 'dart:async';
 import 'dart:io';
 import 'dart:math' as math;
 
 import 'package:args/args.dart';
 import 'package:stack_trace/stack_trace.dart';
 import 'package:yaml/yaml.dart';
 
 import 'backend/test_platform.dart';
 import 'runner/reporter/compact.dart';
+import 'runner/application_exception.dart';
 import 'runner/load_exception.dart';
 import 'runner/load_exception_suite.dart';
 import 'runner/loader.dart';
 import 'util/exit_codes.dart' as exit_codes;
 import 'util/io.dart';
 import 'utils.dart';
 
 /// The argument parser used to parse the executable arguments.
 final _parser = new ArgParser(allowTrailingOptions: true);
 
@@ skipping 212 matching lines @@
       reporter.close().then((_) => timer.cancel());
     });
 
     return reporter.run().then((success) {
       exitCode = success ? 0 : 1;
     }).whenComplete(() {
       signalSubscription.cancel();
       return reporter.close();
     });
   }).whenComplete(signalSubscription.cancel).catchError((error, stackTrace) {
+    if (error is ApplicationException) {
+      stderr.writeln(error.message);
+      exitCode = exit_codes.data;
+      return;
+    }
+
     stderr.writeln(getErrorMessage(error));
     stderr.writeln(new Trace.from(stackTrace).terse);
     stderr.writeln(
         "This is an unexpected error. Please file an issue at "
             "http://github.com/dart-lang/test\n"
         "with the stack trace and instructions for reproducing the error.");
     exitCode = exit_codes.software;
   }).whenComplete(() {
     return loader.close().then((_) {
       // If we're on a Dart version that doesn't support Isolate.kill(), we have
@@ skipping 16 matching lines @@
     output = stderr;
   }
 
   output.write("""$message
 
 Usage: pub run test:test [files or directories...]
 
 ${_parser.usage}
 """);
 }